Fault diagnosis method, device and computer readable storage medium

Abstract

The application relates to the technical field of vehicles, in particular to a fault diagnosis method, equipment and a computer readable storage medium, the method comprising the following steps: determining a secondary voltage generated when fuel is combusted in a target engine cylinder of a target vehicle in a target driving cycle, and detecting whether the secondary voltage is within a preset range; if the secondary voltage is not within the preset range, detecting whether an abnormal duration, in which the secondary voltage is not within the preset range, is greater than a preset duration; and if the abnormal duration is greater than the preset duration, determining that a fault occurs in an ignition system of the target vehicle. In the application, the secondary voltage is used as a basis for judging the fault of the ignition system, so that the fault of the ignition system can be accurately and simply detected, and the normal driving and driving safety of the vehicle are ensured.

Description

Technical Field

[0001] This application relates to the field of vehicle technology, and in particular to a fault diagnosis method, device and computer-readable storage medium. Background Technology

[0002] The ignition system is a crucial component of a vehicle engine. It supplies the spark plugs with sufficient high-voltage electricity at the appropriate time, based on the engine's operating state and sequence, to generate an electric spark between the spark plug electrodes. This spark ignites the fuel in the engine, enabling it to perform work and start the vehicle. During vehicle use, the ignition system may malfunction. For example, reduced ignition performance can cause misfires. A faulty ignition system can prevent the engine from operating normally, thus affecting the vehicle's normal operation and driving safety. Summary of the Invention

[0003] The main purpose of this application is to provide a fault diagnosis method, device and computer-readable storage medium, which aims to diagnose faults in the ignition system and ensure the normal operation and driving safety of the vehicle.

[0004] To achieve the above objectives, this application provides a fault diagnosis method, which includes the following steps:

[0005] Within the target driving cycle, determine the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle, and detect whether the secondary voltage is within a preset range;

[0006] If the secondary voltage is not within the preset range, then it is detected whether the abnormal duration of the secondary voltage not being within the preset range is greater than the preset duration.

[0007] If the duration of the abnormality exceeds the preset duration, it is determined that the ignition system of the target vehicle has malfunctioned.

[0008] Optionally, the step of detecting whether the abnormal duration of the secondary voltage not being within the preset range is greater than a preset duration if the secondary voltage is not within the preset range includes:

[0009] If the secondary voltage is not within the preset range, the voltage anomaly cumulative count is updated, and it is detected whether the updated voltage anomaly cumulative count is greater than the first preset threshold.

[0010] If the updated cumulative voltage anomaly count is less than or equal to the first preset threshold, then it is detected whether the duration of the anomaly where the secondary voltage is not within the preset range is greater than the preset duration.

[0011] Optionally, after the step of detecting whether the updated cumulative voltage anomaly count is greater than a first preset threshold, the method further includes:

[0012] If the number of voltage anomalies exceeds the first preset threshold, the target vehicle is controlled to drive according to a preset torque simulation value until the target driving cycle ends.

[0013] Optionally, after the step of detecting whether the secondary voltage is within a preset range, the method further includes:

[0014] If the secondary voltage is within the preset range, then the voltage anomaly count for the secondary voltage not being within the preset range is initialized, and the process returns to the step of determining the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle and detecting whether the secondary voltage is within the preset range.

[0015] The step of detecting whether the abnormal duration of the secondary voltage not being within the preset range is greater than a preset duration if the secondary voltage is not within the preset range includes:

[0016] If the secondary voltage is within the preset range, the voltage anomaly continuous count is updated, and it is detected whether the updated voltage anomaly continuous count is greater than the second preset threshold.

[0017] If the updated voltage anomaly count is greater than the second preset threshold, then it is determined that the duration of the anomaly where the secondary voltage is outside the preset range is greater than the preset duration.

[0018] If the updated voltage anomaly count is less than or equal to the second preset threshold, then return to the step of determining the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle, and detecting whether the secondary voltage is within the preset range.

[0019] Optionally, after the step of determining that the ignition system of the target vehicle has malfunctioned if the duration of the abnormality is longer than the preset duration, the method further includes:

[0020] The fuel supply to the target engine cylinder is stopped, and the target vehicle is controlled to travel according to a preset safe torque value.

[0021] Optionally, after the steps of stopping fuel supply to the target engine cylinder and controlling the target vehicle to travel at a preset safe torque value, the method further includes:

[0022] Detect whether the target vehicle is in a towing state;

[0023] If the target vehicle is in a reverse towing state, the actual torque value corresponding to the actual vehicle operating condition of the target vehicle is determined, and the target vehicle is controlled to drive according to the actual torque value.

[0024] Optionally, after the step of determining the actual torque value corresponding to the actual vehicle operating condition of the target vehicle if the target vehicle is in a reverse towing state, and controlling the target vehicle to drive according to the actual torque value, the method further includes:

[0025] Update the cumulative count of the target vehicle's resumed driving after being towed, and check whether the updated cumulative count of resumed driving is greater than a third preset threshold;

[0026] If the updated cumulative count of resumed driving is greater than the third preset threshold, the target vehicle is controlled to drive according to the preset torque simulation value until the target driving cycle ends.

[0027] Optionally, the fault diagnosis method further includes:

[0028] If the secondary voltage is greater than the upper limit of the preset range, then the fault type of the ignition system is determined to be an ignition coil fault.

[0029] If the secondary voltage is less than the lower limit of the preset range, the fault type of the ignition system is determined to be a misfire fault.

[0030] To achieve the above objectives, this application also provides a fault diagnosis device, which includes a memory and a processor. The memory stores a fault diagnosis program that can run on the processor. When the fault diagnosis program is executed by the processor, it implements the steps of the fault diagnosis method as described above.

[0031] In addition, to achieve the above objectives, this application also proposes a computer-readable storage medium storing a fault diagnosis program, which, when executed by a processor, implements the steps of the fault diagnosis method as described above.

[0032] In this application, the secondary voltage generated during fuel combustion in the target engine cylinder of a target vehicle is determined within the target driving cycle, and it is detected whether the secondary voltage is within a preset range. If the secondary voltage is not within the preset range, it is detected whether the abnormal duration of the secondary voltage being outside the preset range is greater than a preset duration. If the abnormal duration is greater than the preset duration, it is determined that the ignition system of the target vehicle has malfunctioned. The secondary voltage generated during fuel combustion can accurately reflect the actual working state of the ignition system. This application uses the secondary voltage as the basis for judging ignition system malfunctions, which can accurately and easily detect ignition system malfunctions, thereby ensuring normal vehicle operation and driving safety. Attached Figure Description

[0033] Figure 1This is a schematic diagram of the hardware operating environment involved in the embodiments of this application;

[0034] Figure 2 This is a flowchart illustrating the first embodiment of the fault diagnosis method of this application;

[0035] Figure 3 This is a flowchart illustrating the first embodiment of the fault diagnosis method of this application;

[0036] Figure 4 This is a flowchart illustrating the first embodiment of the fault diagnosis method of this application;

[0037] Figure 5 This is a schematic diagram of the application process involved in one embodiment of the fault diagnosis method of this application;

[0038] Figure 6 This is a schematic diagram of the ignition coil fault diagnosis process according to one embodiment of the fault diagnosis method of this application.

[0039] Figure 7 This is a schematic diagram of the fire fault diagnosis process according to one embodiment of the fault diagnosis method of this application.

[0040] Figure 8 This is a schematic diagram of the functional modules of a preferred embodiment of the fault diagnosis device of this application.

[0041] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0042] It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit this application.

[0043] like Figure 1 As shown, Figure 1 This is a schematic diagram of the device structure of the hardware operating environment involved in the embodiments of this application.

[0044] It should be noted that the fault diagnosis device in this application embodiment can be a smartphone, personal computer, server, or other device, and no specific limitation is made here.

[0045] like Figure 1As shown, the fault diagnosis device may include: a processor 1001, such as a CPU; a network interface 1004; a user interface 1003; a memory 1005; and a communication bus 1002. The communication bus 1002 is used to establish communication between these components. The user interface 1003 may include a display screen and an input unit such as a keyboard; optionally, the user interface 1003 may also include a standard wired interface or a wireless interface. The network interface 1004 may optionally include a standard wired interface or a wireless interface (such as a Wi-Fi interface). The memory 1005 may be high-speed RAM or non-volatile memory, such as a disk drive. Optionally, the memory 1005 may also be a storage device independent of the aforementioned processor 1001.

[0046] Those skilled in the art will understand that Figure 1 The device structure shown does not constitute a limitation on the fault diagnosis device and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0047] like Figure 1 As shown, the memory 1005, as a computer storage medium, may include an operating system, a network communication module, a user interface module, and a fault diagnosis program. The operating system is a program that manages and controls the device's hardware and software resources, supporting the operation of the fault diagnosis program and other software or programs. Figure 1 In the device shown, the user interface 1003 is mainly used for data communication with the client; the network interface 1004 is mainly used for establishing a communication connection with the server; and the processor 1001 can be used to call the fault diagnosis program stored in the memory 1005 and perform the following operations:

[0048] Within the target driving cycle, determine the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle, and detect whether the secondary voltage is within a preset range;

[0049] If the secondary voltage is not within the preset range, then it is detected whether the abnormal duration of the secondary voltage not being within the preset range is greater than the preset duration.

[0050] If the duration of the abnormality exceeds the preset duration, it is determined that the ignition system of the target vehicle has malfunctioned.

[0051] Further, the step of detecting whether the abnormal duration of the secondary voltage not being within the preset range is greater than a preset duration if the secondary voltage is not within the preset range includes:

[0052] If the secondary voltage is not within the preset range, the voltage anomaly cumulative count is updated, and it is detected whether the updated voltage anomaly cumulative count is greater than the first preset threshold.

[0053] If the updated cumulative voltage anomaly count is less than or equal to the first preset threshold, then it is detected whether the duration of the anomaly where the secondary voltage is not within the preset range is greater than the preset duration.

[0054] Furthermore, after the step of detecting whether the updated cumulative voltage anomaly count is greater than the first preset threshold, the processor 1001 can call the fault diagnosis program stored in the memory 1005 and perform the following operations:

[0055] If the number of voltage anomalies exceeds the first preset threshold, the target vehicle is controlled to drive according to a preset torque simulation value until the target driving cycle ends.

[0056] Furthermore, after the step of detecting whether the secondary voltage is within a preset range, the processor 1001 can call the fault diagnosis program stored in the memory 1005 and perform the following operations:

[0057] If the secondary voltage is within the preset range, then the voltage anomaly count for the secondary voltage not being within the preset range is initialized, and the process returns to the step of determining the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle and detecting whether the secondary voltage is within the preset range.

[0058] The step of detecting whether the abnormal duration of the secondary voltage not being within the preset range is greater than a preset duration if the secondary voltage is not within the preset range includes:

[0059] If the secondary voltage is within the preset range, the voltage anomaly continuous count is updated, and it is detected whether the updated voltage anomaly continuous count is greater than the second preset threshold.

[0060] If the updated voltage anomaly count is greater than the second preset threshold, then it is determined that the duration of the anomaly where the secondary voltage is outside the preset range is greater than the preset duration.

[0061] If the updated voltage anomaly count is less than or equal to the second preset threshold, then return to the step of determining the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle, and detecting whether the secondary voltage is within the preset range.

[0062] Furthermore, after the step of determining that the ignition system of the target vehicle has malfunctioned if the duration of the abnormality exceeds the preset duration, the processor 1001 can call the fault diagnosis program stored in the memory 1005 and perform the following operations:

[0063] The fuel supply to the target engine cylinder is stopped, and the target vehicle is controlled to travel according to a preset safe torque value.

[0064] Furthermore, after the steps of stopping fuel supply to the target engine cylinder and controlling the target vehicle to travel at a preset safe torque value, the processor 1001 can call the fault diagnosis program stored in the memory 1005 and perform the following operations:

[0065] Detect whether the target vehicle is in a towing state;

[0066] If the target vehicle is in a reverse towing state, the actual torque value corresponding to the actual vehicle operating condition of the target vehicle is determined, and the target vehicle is controlled to drive according to the actual torque value.

[0067] Furthermore, after the step of determining the actual torque value corresponding to the actual vehicle operating condition of the target vehicle if the target vehicle is in a towing state, and controlling the target vehicle to drive according to the actual torque value, the processor 1001 can be used to call the fault diagnosis program stored in the memory 1005 and perform the following operations:

[0068] Update the cumulative count of the target vehicle's resumed driving after being towed, and check whether the updated cumulative count of resumed driving is greater than a third preset threshold;

[0069] If the updated cumulative count of resumed driving is greater than the third preset threshold, the target vehicle is controlled to drive according to the preset torque simulation value until the target driving cycle ends.

[0070] Furthermore, the processor 1001 can be used to call the fault diagnosis program stored in the memory 1005 and perform the following operations:

[0071] If the secondary voltage is greater than the upper limit of the preset range, then the fault type of the ignition system is determined to be an ignition coil fault.

[0072] If the secondary voltage is less than the lower limit of the preset range, the fault type of the ignition system is determined to be a misfire fault.

[0073] Based on the above structure, various embodiments of the fault diagnosis method are proposed.

[0074] Reference Figure 2 , Figure 2 This is a flowchart illustrating the first embodiment of the fault diagnosis method of this application.

[0075] This application provides an embodiment of a fault diagnosis method. It should be noted that although the flowchart shows a logical order, in some cases, the steps shown or described may be executed in a different order. In this embodiment, the executing entity of the fault diagnosis method can be a personal computer, smartphone, or other device; this is not limited in this embodiment. For ease of description, the execution entity is omitted from the description of each embodiment. In this embodiment, the fault diagnosis method includes:

[0076] Step S10: Determine the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle, and detect whether the secondary voltage is within a preset range.

[0077] In this embodiment, the vehicle undergoing ignition system fault diagnosis is referred to as the target vehicle. The complete process of the target vehicle completing ignition, operation, and shutdown is referred to as a driving cycle. In this embodiment, the ignition system fault diagnosis of the target vehicle is performed in each driving cycle to detect ignition system faults in a timely manner and improve the driving safety of the target vehicle. For ease of description, any driving cycle will be referred to as the target driving cycle.

[0078] The target vehicle's engine typically has multiple cylinders, each equipped with at least one spark plug. Hereinafter, any one of these cylinders will be referred to as the target engine cylinder for distinction. The ignition system, composed of components such as ignition coils, spark plugs, and sensors, is used to ignite the fuel in the engine, thereby driving the target vehicle. During combustion, the fuel generates a stream of charged ions; the voltage produced by this stream is the secondary voltage. When components such as the ignition coil and spark plugs in the ignition system malfunction or fail, the secondary voltage will exceed the normal range. Therefore, the secondary voltage can be used to determine faults in the vehicle's ignition system.

[0079] Specifically, in this embodiment, the secondary voltage of the target engine cylinder in the ignition system of the target vehicle is obtained within the target driving cycle to diagnose faults in the ignition system based on the secondary voltage. There are various ways to obtain the secondary voltage, which are not limited here. In one feasible embodiment, the secondary voltage can be obtained by setting a voltage sensor; in another feasible embodiment, the secondary voltage can be obtained by querying the current engine speed and current engine coolant temperature of the target vehicle, and then querying a preset engine operating condition table based on these parameters. The engine operating condition table contains the engine's operating parameters under different conditions, such as engine speed, coolant temperature, accelerator pedal position, and vehicle speed. By querying the engine operating condition table, the secondary voltage corresponding to engine operation under different conditions can be obtained. The engine operating condition table can be obtained through experiments and tests, and is not limited here.

[0080] In this embodiment, a normal range for the secondary voltage is preset, hereinafter referred to as the preset range for distinction. After acquiring the secondary voltage, it is checked whether the secondary voltage is within the preset range to determine whether the secondary voltage is normal, thereby determining whether the ignition system has malfunctioned. In specific implementations, the preset range can be set according to the target vehicle model, actual operating conditions, and / or actual needs, and is not limited here. For example, the general range of the secondary voltage is 10 to 1000V, and the preset range can be set to 10 to 1000V.

[0081] Step S20: If the secondary voltage is not within the preset range, then detect whether the abnormal duration of the secondary voltage not being within the preset range is greater than the preset duration.

[0082] A secondary voltage outside the preset range may be caused by an ignition system malfunction or an intermittent malfunction such as engine overheating. Ignition system malfunctions are usually difficult to self-heal, so ignition system malfunctions may cause abnormal secondary voltage (i.e., the secondary voltage is outside the preset range) to last for a long time. Intermittent malfunctions, on the other hand, can usually recover on their own, and the abnormal secondary voltage caused by intermittent malfunctions is temporary.

[0083] In this embodiment, the continuous duration from the moment the secondary voltage is determined to be outside the preset range is called the abnormal duration. By detecting whether the abnormal duration is greater than the preset duration, it is determined whether the secondary voltage being outside the preset range is caused by an ignition system malfunction. This embodiment can eliminate the interference of intermittent faults on ignition system malfunctions and improve the accuracy of ignition system fault diagnosis.

[0084] Specifically, the process of detecting whether the duration of the abnormality is greater than the preset duration is not limited here. For example, in one feasible implementation, timing can be started from the moment when the secondary voltage is determined to be outside the preset range, and the obtained duration can be used as the duration of the abnormality for detection. In another feasible implementation, the time when the secondary voltage is outside the preset range can be counted, and whether the duration of the abnormality is greater than the preset duration can be detected by detecting whether the number obtained by counting is greater than the preset number.

[0085] Step S30: If the duration of the abnormality is longer than the preset duration, it is determined that the ignition system of the target vehicle has malfunctioned.

[0086] If the duration exceeds the preset duration, it indicates that the secondary voltage is outside the preset range and this phenomenon has persisted for a considerable period of time. In this case, it can be determined that the ignition system is faulty rather than an intermittent fault. That is, if the duration exceeds the preset duration, the ignition system is faulty.

[0087] Furthermore, in one feasible implementation, when an ignition system malfunction is determined, safety measures can be taken for the target vehicle to ensure that the target vehicle can drive safely when the ignition system malfunctions, thereby improving vehicle safety. For example, measures such as limiting torque and shutting down the malfunctioning engine cylinder can be taken, and the vehicle can also be controlled to stop running.

[0088] Furthermore, in one feasible embodiment, when an ignition system fault is determined, different safety measures can be taken for the target vehicle depending on the severity of the ignition system fault. For example, in one feasible embodiment, a reference value can be determined based on a preset range. The reference value is not limited and can be the median, upper limit, or lower limit of the preset range. The voltage difference between the secondary voltage and the reference value is calculated, wherein the absolute value of the voltage difference is proportional to the severity of the ignition system fault. In this embodiment, when the voltage difference exceeds the preset difference range, the severity of the ignition system fault is determined to be high, and the target vehicle can be stopped. It should be noted that stopping the target vehicle can be achieved by gradually reducing the vehicle's speed to avoid sudden stopping that could threaten user safety. When the deviation value is less than the deviation range, the severity of the ignition system fault is determined to be low, and measures such as shutting down the faulty engine cylinder and limiting torque can be taken for the target vehicle.

[0089] Furthermore, in one feasible implementation, if the duration is less than or equal to a preset duration, it is determined that the abnormality of the secondary voltage is caused by an intermittent fault, and the ignition system is considered not to have malfunctioned. That is, if the duration is less than or equal to the preset duration, it is determined that the ignition system has not malfunctioned.

[0090] Furthermore, in one feasible embodiment, the fault diagnosis method further includes steps S40-S50.

[0091] Step S40: If the secondary voltage is greater than the upper limit of the preset range, then the fault type of the ignition system is determined to be an ignition coil fault.

[0092] Ignition coil failure refers to a fault where the ignition coil generates additional current during ignition, resulting in excessively high secondary current. This could be caused by excessive carbon buildup on the spark plug, a short circuit in the spark plug, or a short circuit in the ignition coil. In this embodiment, if the secondary voltage exceeds the upper limit of a preset range, it can be determined that the high voltage generated by the ignition coil is too high. That is, if the secondary voltage exceeds the upper limit of the preset range, the fault type of the ignition system is determined to be an ignition coil failure.

[0093] Step S50: If the secondary voltage is less than the lower limit of the preset range, then the fault type of the ignition system is determined to be a misfire fault.

[0094] A misfire is a fault in which the ignition system's ignition performance is reduced, resulting in incomplete combustion of fuel in the engine cylinders. Misfires can be caused by factors such as spark plug aging. When a misfire occurs, the fuel in the engine cylinders cannot burn completely, and the secondary voltage may be lower than a preset range. In this embodiment, if the secondary voltage is lower than the lower limit of the preset range, the ignition system fault type is determined to be a misfire.

[0095] In this embodiment, by distinguishing the types of ignition system faults, the time required for engineers to perform repairs is reduced, thereby improving repair efficiency.

[0096] In this embodiment, the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle is determined within the target driving cycle, and it is detected whether the secondary voltage is within a preset range. The target engine cylinder can be any engine cylinder in the target vehicle. If the secondary voltage is not within the preset range, the abnormal duration of the non-preset voltage is detected to be greater than a preset duration. If the abnormal duration is greater than the preset duration, it is determined that the ignition system of the target vehicle has malfunctioned. The secondary voltage generated during fuel combustion can accurately reflect the actual working state of the ignition system. In this embodiment, using the secondary voltage as the basis for judging ignition system malfunctions can accurately and easily detect ignition system faults, thereby ensuring normal vehicle operation and driving safety.

[0097] Furthermore, based on the first embodiment described above, a second embodiment of the fault diagnosis method of the present invention is proposed, referring to... Figure 3In this embodiment, step S20: if the secondary voltage is not within the preset range, then detect whether the abnormal duration of the secondary voltage not being within the preset range is greater than the preset duration, including steps S201-S202.

[0098] Step S201: If the secondary voltage is not within the preset range, update the cumulative voltage anomaly count and check whether the updated cumulative voltage anomaly count is greater than the first preset threshold.

[0099] Ignition system malfunctions can be classified as recoverable or unrecoverable. A recoverable malfunction is one that, after being addressed with safety measures, allows the vehicle to operate under normal conditions. An unrecoverable malfunction is one that, after being addressed with safety measures, prevents the vehicle from operating under normal conditions.

[0100] In this embodiment, the number of times the ignition system of the target vehicle experiences voltage abnormalities within the target driving cycle is accumulated. For ease of description, the accumulated number of voltage abnormalities within the target driving cycle is referred to as the voltage abnormality cumulative count. Specifically, in this embodiment, when the secondary voltage of the target vehicle is outside the preset range, it is determined that the ignition system of the target vehicle has experienced a voltage abnormality, and the voltage abnormality cumulative count is updated.

[0101] The system checks whether the updated cumulative voltage anomaly count exceeds a first preset threshold. By checking whether the cumulative voltage anomaly count exceeds the preset threshold, the frequency of voltage anomalies in the target vehicle within the target driving cycle can be assessed, thereby evaluating the reliability and safety of the target vehicle's ignition system. Specifically, the first preset threshold can be set according to actual needs and is not limited here.

[0102] Step S202: If the updated cumulative voltage anomaly count is less than or equal to the first preset threshold, then detect whether the duration of the anomaly where the secondary voltage is not within the preset range is greater than the preset duration.

[0103] In this embodiment, if the updated cumulative voltage anomaly count is less than or equal to the first preset threshold, it is determined that the frequency of voltage anomalies in the ignition system of the target vehicle is low and the ignition system has not experienced an irreversible fault. At this time, it is detected whether the duration of the anomaly of the secondary voltage not being within the preset range exceeds the preset duration.

[0104] By detecting whether the duration of the abnormality exceeds a preset time, it can be determined whether the voltage abnormality in the ignition system is caused by a recoverable fault or is an intermittent voltage abnormality. The specific detection process will not be described in detail here, but can be referred to the first embodiment.

[0105] Furthermore, in one feasible embodiment, after step S201: detecting whether the updated cumulative voltage anomaly count is greater than the first preset threshold, step S203 is also included.

[0106] Step S203: If the number of voltage anomalies is greater than the first preset threshold, then control the target vehicle to drive according to the preset torque simulation value until the target driving cycle ends.

[0107] In this embodiment, a torque value that allows the target vehicle to drive safely is preset, hereinafter referred to as the preset torque simulation value for distinction. The torque simulation value can be obtained through experiments and tests, or it can be set according to actual needs; there are no restrictions here.

[0108] If the cumulative count of voltage anomalies exceeds the first preset threshold, it is determined that the ignition system of the target vehicle has an irreversible fault. Then, the target vehicle is controlled to drive according to the preset torque simulation value until the target driving cycle ends. In this embodiment, the target vehicle does not operate according to the actual operating conditions of the vehicle during the target driving cycle, but operates according to the preset safe torque value to ensure the driving safety of the target vehicle.

[0109] Furthermore, in a feasible embodiment, measures such as open-loop control, torque limiting, lean combustion, EGR valve closure, and fuel cut-off can be implemented on the target vehicle to control it to drive according to a preset torque simulation value. In this embodiment, these measures can improve fuel combustion efficiency and power performance. Specifically, open-loop control refers to establishing an open channel between the engine's exhaust gases and the air entering the engine, allowing both exhaust gases and air to freely enter the exhaust gases; torque limiting refers to reducing the amount of combustion by limiting the engine's torque output during operation; lean combustion refers to adjusting the engine's air-fuel mixture to a lean state, resulting in insufficient mixing of air and fuel; closing the EGR (Exhaust Gas Recirculation) valve means stopping the exhaust gas recirculation process; and fuel cut-off refers to cutting off the fuel supply during engine operation.

[0110] This implementation method enables the target vehicle to drive at a preset safe torque when an unrecoverable ignition system failure is detected, thus ensuring that the target vehicle can drive safely when the ignition system fails.

[0111] Furthermore, in one feasible embodiment, after step S10: detecting whether the secondary voltage is within a preset range, step S60 is also included.

[0112] Step S60: If the secondary voltage is within the preset range, initialize the continuous counting of voltage anomalies where the secondary voltage is not within the preset range, and return to the step of determining the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle and detecting whether the secondary voltage is within the preset range.

[0113] In this embodiment, the number of consecutive occurrences of secondary voltage anomalies is accumulated, and for convenience, this is referred to as voltage anomaly continuity count. The duration of the voltage anomaly is evaluated by the voltage anomaly continuity count.

[0114] Specifically, in this embodiment, if the secondary voltage is within a preset range, the voltage is determined to be normal. At this time, the voltage anomaly continuous count is initialized to ensure that the voltage anomaly continuous count represents continuously occurring voltage anomalies, thereby improving the accuracy of fault diagnosis of the power system.

[0115] After initializing the continuous counting of voltage anomalies where the secondary voltage is not within the preset range, the secondary voltage of the ignition system is checked again. That is, the process returns to the step of determining the secondary voltage generated when fuel is burned in the target engine cylinder of the target vehicle within the target driving cycle and checking whether the secondary voltage is within the preset range.

[0116] In this embodiment, step S20: if the secondary voltage is not within the preset range, then detect whether the abnormal duration of the secondary voltage not being within the preset range is greater than the preset duration, including steps S204-S206.

[0117] Step S204: If the secondary voltage is not within the preset range, update the voltage anomaly continuous count for the secondary voltage not within the preset range, and detect whether the updated voltage anomaly continuous count is greater than the second preset threshold.

[0118] In this embodiment, if the secondary voltage is not within the preset range, the secondary voltage is determined to be abnormal, and the voltage abnormality continuous count is updated.

[0119] The system detects whether the continuous count of abnormal voltage events exceeds a second preset threshold, thereby detecting whether the duration of the abnormality exceeds a preset duration. Specifically, the second preset threshold can be further set according to actual needs and is not limited here.

[0120] Step S205: If the updated voltage anomaly count is greater than the second preset threshold, then it is determined that the duration of the anomaly of the secondary voltage not being within the preset range is greater than the preset duration.

[0121] If the consecutive count of voltage anomalies exceeds the second preset threshold, it is determined that the secondary voltage has been abnormal multiple times. In other words, it is determined that the duration of the abnormality of the secondary voltage outside the preset range is longer than the preset duration.

[0122] Step S206: If the updated voltage anomaly consecutive count is less than or equal to the second preset threshold, then return to the step of determining the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle, and detecting whether the secondary voltage is within the preset range.

[0123] In this embodiment, if the consecutive count of voltage abnormalities is less than or equal to the second preset threshold, it is determined that the duration of the voltage abnormality has not yet reached the preset duration. At this time, the secondary voltage of the ignition system is detected again. That is, the process returns to the step of determining the secondary voltage generated when fuel is burned in the target engine cylinder of the target vehicle within the target driving cycle and detecting whether the secondary voltage is within the preset range.

[0124] In this embodiment, if the secondary voltage is outside a preset range, the system increments the voltage anomaly count and then checks if the accumulated voltage anomaly count is greater than a first preset threshold. If the accumulated voltage anomaly count is less than or equal to the first preset threshold, the system checks if the duration of the voltage anomaly outside the preset range is greater than a preset duration. This embodiment enables the detection of unrecoverable faults in the ignition system, ensuring the safety of the target vehicle during driving.

[0125] Furthermore, based on the first and / or second embodiments described above, a third embodiment of the fault diagnosis method of the present invention is proposed, referring to... Figure 4 In this embodiment, step S30: if the duration of the abnormality is longer than the preset duration, then after determining that the ignition system of the target vehicle has malfunctioned, step S70 is also included.

[0126] In step S70, fuel supply to the target engine cylinder is stopped, and the target vehicle is controlled to travel according to a preset safe torque value.

[0127] In this embodiment, after determining that the ignition system is malfunctioning, it is necessary to stop supplying fuel to the target engine cylinders to prevent them from affecting the driving safety of the target vehicle. The target vehicle is controlled to drive at a preset safe torque value to ensure its driving safety.

[0128] Furthermore, in one feasible embodiment, after step S70: cutting off the fuel supply to the target engine cylinder and controlling the target vehicle to travel according to the preset safe torque value, the method further includes steps S80-S90.

[0129] Step S80: Detect whether the target vehicle is in a reverse towing state.

[0130] The overrun state refers to a state where the engine is not injecting or receiving fuel, but the engine is still running. In specific implementations, there are multiple ways to determine whether the target vehicle is in the overrun state, which are not limited here. For example, in one feasible implementation, the target vehicle can be determined to be in the overrun state when the engine speed is less than the input shaft speed of the automatic transmission.

[0131] Step S90: If the target vehicle is in a reverse towing state, determine the actual torque value corresponding to the actual vehicle operating condition of the target vehicle, and control the target vehicle to drive according to the actual torque value.

[0132] In this embodiment, when it is determined that the target vehicle is in a reverse towing state, the target vehicle is controlled to operate according to the actual vehicle operating conditions. That is, if the target vehicle is in a reverse towing state, the actual torque value corresponding to the actual vehicle operating conditions of the target vehicle is determined, and the target vehicle is controlled to drive according to the actual torque value.

[0133] The process of determining the actual torque value corresponding to the actual vehicle operating conditions of the target vehicle is not limited here. For example, in one feasible implementation, the actual torque value can be obtained by querying a preset vehicle operating condition table, wherein the vehicle operating condition table contains the torque of the target vehicle under different operating conditions. The vehicle operating condition table can be obtained through experiments and tests, and is not limited here.

[0134] Further, in one feasible implementation, step S90: if the target vehicle is in a reverse towing state, then after determining the actual torque value corresponding to the actual vehicle operating condition of the target vehicle, and controlling the target vehicle to drive according to the actual torque value, further includes steps SA10-A20.

[0135] Step A10: Update the cumulative count of the target vehicle's resumed driving after being towed, and check whether the updated cumulative count of resumed driving is greater than a third preset threshold.

[0136] In this embodiment, the number of times the target vehicle resumes driving after being towed is referred to as the cumulative count of resumed driving for ease of description.

[0137] By detecting whether the updated cumulative count of resumed driving exceeds a third preset threshold, the frequency of a target vehicle resuming driving after a recoverable fault can be determined. This helps determine whether the target vehicle frequently experiences recoverable faults, thereby assessing its driving reliability and safety. Specifically, the third preset threshold is not limited here and can be set according to actual needs.

[0138] Step A20: If the cumulative count of resumed driving is greater than the third preset threshold, then control the target vehicle to drive according to the preset torque simulation value until the target driving cycle ends.

[0139] If the cumulative count of resumed driving exceeds the third preset threshold, the target vehicle will be controlled to drive according to the preset torque simulation value until the target driving cycle ends.

[0140] Furthermore, in one feasible implementation, if the cumulative driving count is less than or equal to a third preset threshold, the process returns to the step of determining the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle and detecting whether the secondary voltage is within a preset range.

[0141] In this embodiment, after determining that the ignition system of the target vehicle has failed, the fuel supply to the target engine cylinders is cut off, and the target vehicle is controlled to drive according to a preset safe torque value. This embodiment ensures that the target vehicle can drive safely when the ignition system fails.

[0142] Exemplarily, in one feasible implementation, reference is made to Figure 5 The specific process of fault diagnosis can be as follows:

[0143] Within the target driving cycle, the secondary voltage of the target engine cylinder is acquired (that is, the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle is determined within the target driving cycle).

[0144] The system checks whether the secondary voltage is within a preset range. If the secondary voltage is within the preset range, the system sets the number of consecutive times the secondary voltage is outside the preset range, A, to 0 (i.e., if the secondary voltage is within the preset range, the system initializes the voltage anomaly count for the secondary voltage being outside the preset range and returns to the step of determining the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle and checking whether the secondary voltage is within the preset range). If the secondary voltage is outside the preset range, the system sets the number of consecutive times the secondary voltage is greater than the preset range, A, to A+1 (i.e., if the secondary voltage is within the preset range, the system updates the voltage anomaly count), and sets the cumulative count of the secondary voltage being greater than the preset range, B, to B+1 (i.e., if the secondary voltage is outside the preset range, the system updates the cumulative voltage anomaly count).

[0145] Check if B is greater than 100 (i.e., check if the cumulative voltage anomaly count is greater than the first preset threshold). If B is greater than 100, then open-loop control, torque limiting, lean fuel, EGR valve closed, fuel cut-off until the target driving cycle ends (i.e., if the number of voltage anomalies is greater than the first preset threshold, then control the target vehicle to drive according to the preset torque simulation value until the target driving cycle ends); if B is less than or equal to 100, then check if A is greater than 5 (i.e., if the updated cumulative voltage anomaly count is less than or equal to the first preset threshold, then check if the updated continuous voltage anomaly count is greater than the second preset threshold).

[0146] If A is less than or equal to 5, then return to obtain the secondary voltage of the target engine cylinder (that is, if the updated voltage abnormality consecutive count is less than or equal to the second preset threshold, then return to execute the step of determining the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle and checking whether the secondary voltage is within the preset range).

[0147] If A is greater than 5, an ignition coil fault is confirmed, and the vehicle travels according to the preset safe torque value (that is, if the updated voltage abnormality continuous count is greater than the second preset threshold, it is determined that the duration of the abnormality of the secondary voltage outside the preset range is greater than the preset duration, fuel supply to the target engine cylinder is stopped, and the target vehicle is controlled to travel according to the preset safe torque value). After the vehicle overruns, the vehicle is controlled to travel according to the actual operating conditions, and the cumulative count of recovery after overruns is C = C + 1 (that is, if the target vehicle is in a towing state, after determining the actual torque value corresponding to the actual vehicle operating conditions of the target vehicle, controlling the target vehicle to travel according to the actual torque value, the cumulative count of recovery after the target vehicle is towed is updated).

[0148] Check if C is greater than 3 (that is, check if the updated cumulative count of resumed driving is greater than the third preset threshold).

[0149] If C is greater than 3, then open loop, limit torque, lean fuel, close EGR valve, cut off fuel until the target driving cycle ends (that is, if the updated cumulative count of resumed driving is greater than the third preset threshold, then control the target vehicle to drive according to the preset torque simulation value until the target driving cycle ends); if C is less than or equal to 3, then return to obtain the secondary voltage of the target engine cylinder.

[0150] For example, in one feasible implementation, the specific process of fault diagnosis may be:

[0151] S1: Within the target driving cycle, acquire the secondary voltage of the target engine cylinder.

[0152] S2: Detect whether the secondary voltage is within the preset range.

[0153] If the secondary voltage is within the preset range, then set the number of consecutive times the secondary voltage is greater than the upper limit value i = 0, and set the number of consecutive times the secondary voltage is less than the lower limit value j = 0, and return to S1 (that is, if the secondary voltage is within the preset range, then initialize the continuous count of voltage anomalies where the secondary voltage is not within the preset range, and return to execute the step of determining the secondary voltage generated when the fuel is burned in the target engine cylinder of the target vehicle within the target driving cycle, and checking whether the secondary voltage is within the preset range).

[0154] If the secondary voltage is not within the preset range and the secondary voltage is greater than the upper limit of the preset range, then execute S3-S11. If the secondary voltage is not within the preset range and the secondary voltage is less than the upper limit of the preset range, then execute S12-19.

[0155] Specifically, refer to Figure 6 If the secondary voltage is not within the preset range and the secondary voltage is greater than the upper limit of the preset range, then execute S3-S10 as follows:

[0156] S3: The number of consecutive times the secondary voltage is greater than the upper limit value i = i + 1 (that is, the continuous count of updated voltage anomalies), and the cumulative count of the secondary voltage being greater than the upper limit value p = p + 1 (that is, the cumulative count of updated voltage anomalies).

[0157] S4: Detect whether p is greater than 100 (that is, detect whether the cumulative voltage anomaly count is greater than the first preset threshold). If p is greater than 100, then execute S5 (that is, if the cumulative voltage anomaly count is less than or equal to the first preset threshold, then detect whether the duration of the secondary voltage anomaly outside the preset range is greater than the preset duration); if p is less than or equal to 100, then execute S11 (that is, if the cumulative voltage anomaly count is greater than the first preset threshold, then control the target vehicle to drive according to the preset torque simulation value until the target driving cycle ends).

[0158] S5: Detect whether i is greater than 5 (that is, detect whether the continuous voltage anomaly count is greater than the second preset threshold). If i is greater than 5, then execute S6 (that is, if the continuous voltage anomaly count is greater than the second preset threshold, then determine that the duration of the anomaly of the secondary voltage outside the preset range is longer than the preset duration, and determine that the ignition system of the target vehicle has failed); if i is less than or equal to 5, then execute S1 (that is, if the updated continuous voltage anomaly count is less than or equal to the second preset threshold, then return to the step of determining the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle, and detecting whether the secondary voltage is within the preset range).

[0159] S6: If an ignition coil malfunction is detected, drive according to the preset safe torque value (that is, stop supplying fuel to the target engine cylinder and control the target vehicle to drive according to the preset safe torque value), then proceed to S7.

[0160] S7: After the vehicle overruns, control the vehicle to drive according to the actual working conditions, then switch to S9 (that is, if the target vehicle is in a towing state, determine the actual torque value corresponding to the actual vehicle working conditions of the target vehicle, and control the target vehicle to drive according to the actual torque value).

[0161] S8: The cumulative count of recovery after overrun is M = M + 1 (that is, the cumulative count of recovery of driving after the target vehicle is towed back), then proceed to S9.

[0162] S9: Is M greater than 3 (that is, check if the cumulative count of resumed driving is greater than the third preset threshold). If M is greater than 3, then execute S11 (that is, if the cumulative count of resumed driving is greater than the third preset threshold, then control the target vehicle to drive according to the preset torque simulation value until the target driving cycle ends); if M is less than or equal to 3, then return to execute S1.

[0163] S10: Open loop, torque limiting, lean combustion, EGR valve closed, fuel cut-off until the target driving cycle ends.

[0164] Specifically, refer to Figure 7 If the secondary voltage is not within the preset range and the secondary voltage is less than the upper limit of the preset range, then S11-18 is executed as follows:

[0165] S11: The number of consecutive times the secondary voltage is less than the lower limit is j = j + 1 (that is, the continuous count of updated voltage anomalies), and the cumulative count of the secondary voltage being greater than the upper limit is q = q + 1 (that is, the cumulative count of updated voltage anomalies).

[0166] S12: Detect whether q is greater than 100 (that is, detect whether the cumulative voltage anomaly count is greater than the first preset threshold). If q is greater than 100, then execute S14 (that is, if the cumulative voltage anomaly count is less than or equal to the first preset threshold, then detect whether the duration of the secondary voltage anomaly outside the preset range is greater than the preset duration); if q is less than or equal to 100, then execute S11 (that is, if the cumulative voltage anomaly count is greater than the first preset threshold, then control the target vehicle to drive according to the preset torque simulation value until the target driving cycle ends).

[0167] S13: Detect whether j is greater than 5 (that is, detect whether the continuous voltage anomaly count is greater than the second preset threshold). If j is greater than 5, then execute S15 (that is, if the continuous voltage anomaly count is greater than the second preset threshold, then determine that the duration of the secondary voltage anomaly outside the preset range is greater than the preset duration, and determine that the ignition system of the target vehicle has malfunctioned); if j is less than or equal to 5, then execute S1 (that is, if the updated continuous voltage anomaly count is less than or equal to the second preset threshold, then return to the step of determining the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle, and detecting whether the secondary voltage is within the preset range).

[0168] S14: If a misfire is detected, drive according to the preset safe torque value (that is, stop supplying fuel to the target engine cylinder and control the target vehicle to drive according to the preset safe torque value), then proceed to S15.

[0169] S15: After the vehicle overruns, control the vehicle to drive according to the actual working conditions (that is, if the target vehicle is in a towing state, determine the actual torque value corresponding to the actual vehicle working conditions of the target vehicle, and control the target vehicle to drive according to the actual torque value), and then proceed to S18.

[0170] S16: The cumulative count N after overrun is N+1 (that is, the cumulative count of driving resumed after the target vehicle is towed back), then proceed to S17.

[0171] S17: Is M greater than 3 (that is, check if the cumulative count of resumed driving is greater than the third preset threshold). If M is greater than 3, then execute S11 (that is, if the cumulative count of resumed driving is greater than the third preset threshold, then control the target vehicle to drive according to the preset torque simulation value until the target driving cycle ends); if M is less than or equal to 3, then return to execute S1.

[0172] S18: Open loop, torque limiting, lean combustion, EGR valve closed, fuel cut-off until the target driving cycle ends.

[0173] In other words, in this embodiment, the specific process of fault diagnosis can be:

[0174] (1) Check whether the secondary voltage is within the preset range.

[0175] (2) When the secondary voltage value of the target engine cylinder is higher than the upper limit of the preset range, the ignition system fault corresponds to an ignition coil fault, specifically:

[0176] I. If the secondary voltage of the target engine cylinder exceeds the upper limit after 5 consecutive ignition cycles, measures such as open-loop control, torque limiting, lean combustion, EGR valve closure, and fuel cut-off will be implemented. The problem can be cured and recovered after the target driving cycle overrun.

[0177] II. If the above-mentioned fault occurs within the target driving cycle and the fault recurs after 3 overruns, then when the fault occurs for the 4th time, the fault measures will continue until the machine is shut down, and recovery will not be allowed.

[0178] III. When the secondary voltage of the target engine cylinder exceeds the upper limit 100 times in total, measures such as open-loop control, torque limiting, lean combustion, closing the EGR valve, and cutting off fuel will be implemented directly until the engine is shut down. Recovery is not allowed.

[0179] (3) When the secondary voltage value of the target engine cylinder is lower than the lower limit of the preset range, the ignition system fault corresponds to a misfire fault, specifically:

[0180] I. If the secondary voltage of the target engine cylinder falls below the lower limit after five consecutive ignition cycles, measures such as open-loop control, torque limiting, lean combustion, EGR valve closure, and fuel cut-off will be implemented. The problem can be cured and recovered after the target driving cycle overrun.

[0181] II. If the above-mentioned fault occurs within the target driving cycle and the fault recurs after 3 overruns, then when the fault occurs for the 4th time, the fault measures will continue until the machine is shut down, and recovery will not be allowed.

[0182] III. When the secondary voltage of the target engine cylinder falls below the lower limit 100 times in total, measures such as open-loop control, torque limiting, lean combustion, EGR valve closure, and fuel cut-off will be implemented directly until the engine is shut down. Recovery is not allowed.

[0183] Furthermore, this application also proposes a fault diagnosis device, referring to... Figure 8 The fault diagnosis device includes:

[0184] The first detection module 10 is used to determine the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle, and to detect whether the secondary voltage is within a preset range.

[0185] The second detection module 20 is used to detect whether the abnormal duration of the secondary voltage not being in the preset range is greater than a preset duration if the secondary voltage is not in the preset range.

[0186] The determination module 30 is used to determine that the ignition system of the target vehicle has malfunctioned if the duration of the abnormality is longer than the preset duration.

[0187] Furthermore, the second detection module 20 is also used for:

[0188] If the secondary voltage is not within the preset range, the voltage anomaly cumulative count is updated, and it is detected whether the updated voltage anomaly cumulative count is greater than the first preset threshold.

[0189] If the updated cumulative voltage anomaly count is less than or equal to the first preset threshold, then it is detected whether the duration of the anomaly where the secondary voltage is not within the preset range is greater than the preset duration.

[0190] Furthermore, the second detection module 20 is also used for:

[0191] If the number of voltage anomalies exceeds the first preset threshold, the target vehicle is controlled to drive according to a preset torque simulation value until the target driving cycle ends.

[0192] Furthermore, the fault diagnosis method also includes an initialization module, used for:

[0193] If the secondary voltage is within the preset range, then the voltage anomaly count for the secondary voltage not being within the preset range is initialized, and the process returns to the step of determining the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle and detecting whether the secondary voltage is within the preset range.

[0194] The second detection module 20 is also used for:

[0195] If the secondary voltage is within the preset range, the voltage anomaly continuous count is updated, and it is detected whether the updated voltage anomaly continuous count is greater than the second preset threshold.

[0196] If the updated voltage anomaly count is greater than the second preset threshold, then it is determined that the duration of the anomaly where the secondary voltage is outside the preset range is greater than the preset duration.

[0197] If the updated voltage anomaly count is less than or equal to the second preset threshold, then return to the step of determining the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle, and detecting whether the secondary voltage is within the preset range.

[0198] Furthermore, the fault diagnosis method also includes a control module, used for:

[0199] The fuel supply to the target engine cylinder is stopped, and the target vehicle is controlled to travel according to a preset safe torque value.

[0200] Furthermore, the fault diagnosis method also includes a drag-back recovery module, used for:

[0201] Detect whether the target vehicle is in a towing state;

[0202] If the target vehicle is in a reverse towing state, the actual torque value corresponding to the actual vehicle operating condition of the target vehicle is determined, and the target vehicle is controlled to drive according to the actual torque value.

[0203] Furthermore, the fault diagnosis method also includes a third detection module, used for:

[0204] Update the cumulative count of the target vehicle's resumed driving after being towed, and check whether the updated cumulative count of resumed driving is greater than a third preset threshold;

[0205] If the updated cumulative count of resumed driving is greater than the third preset threshold, the target vehicle is controlled to drive according to the preset torque simulation value until the target driving cycle ends.

[0206] Furthermore, the fault diagnosis method further includes a fault diagnosis module, used for:

[0207] If the secondary voltage is greater than the upper limit of the preset range, then the fault type of the ignition system is determined to be an ignition coil fault.

[0208] If the secondary voltage is less than the lower limit of the preset range, the fault type of the ignition system is determined to be a misfire fault.

[0209] All embodiments of the fault diagnosis device of this application can refer to the various embodiments of the fault diagnosis method of this application, and will not be repeated here.

[0210] Furthermore, embodiments of this application also propose a computer-readable storage medium storing a fault diagnosis program, which, when executed by a processor, implements the steps of the fault diagnosis method described below.

[0211] The various embodiments of the fault diagnosis device and computer-readable storage medium of this application can be referred to the various embodiments of the fault diagnosis method of this application, and will not be repeated here.

[0212] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0213] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0214] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk), and includes several instructions to cause a terminal device (which may be a mobile phone, computer, server, air conditioner, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0215] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A fault diagnosis method, characterized in that, The fault diagnosis method includes the following steps: Within the target driving cycle, determine the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle, and detect whether the secondary voltage is within a preset range; If the secondary voltage is not within the preset range, then it is detected whether the abnormal duration of the secondary voltage not being within the preset range is greater than the preset duration. If the duration of the abnormality exceeds the preset duration, it is determined that the ignition system of the target vehicle has malfunctioned. The step of detecting whether the abnormal duration of the secondary voltage not being within the preset range is greater than a preset duration if the secondary voltage is not within the preset range includes: If the secondary voltage is not within the preset range, the voltage anomaly cumulative count is updated, and it is detected whether the updated voltage anomaly cumulative count is greater than the first preset threshold. If the updated cumulative voltage anomaly count is less than or equal to the first preset threshold, then it is detected whether the duration of the anomaly where the secondary voltage is not within the preset range is greater than the preset duration. The step of detecting whether the updated cumulative voltage anomaly count is greater than a first preset threshold further includes: If the number of voltage anomalies exceeds the first preset threshold, the target vehicle is controlled to drive according to a preset torque simulation value until the target driving cycle ends.

2. The fault diagnosis method as described in claim 1, characterized in that, After the step of detecting whether the secondary voltage is within a preset range, the method further includes: If the secondary voltage is within the preset range, then the voltage anomaly count for the secondary voltage not being within the preset range is initialized, and the process returns to the step of determining the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle and detecting whether the secondary voltage is within the preset range. The step of detecting whether the abnormal duration of the secondary voltage not being within the preset range is greater than a preset duration if the secondary voltage is not within the preset range includes: If the secondary voltage is within the preset range, the voltage anomaly continuous count is updated, and it is detected whether the updated voltage anomaly continuous count is greater than the second preset threshold. If the updated voltage anomaly count is greater than the second preset threshold, then it is determined that the duration of the anomaly where the secondary voltage is outside the preset range is greater than the preset duration. If the updated voltage anomaly count is less than or equal to the second preset threshold, then return to the step of determining the secondary voltage generated during fuel combustion in the target engine cylinder of the target vehicle within the target driving cycle, and detecting whether the secondary voltage is within the preset range.

3. The fault diagnosis method as described in claim 1, characterized in that, After the step of determining that the ignition system of the target vehicle has malfunctioned if the duration of the abnormality is longer than the preset duration, the method further includes: The fuel supply to the target engine cylinder is stopped, and the target vehicle is controlled to travel according to a preset safe torque value.

4. The fault diagnosis method as described in claim 3, characterized in that, After the steps of stopping fuel supply to the target engine cylinder and controlling the target vehicle to travel at a preset safe torque value, the method further includes: Detect whether the target vehicle is in a towing state; If the target vehicle is in a reverse towing state, the actual torque value corresponding to the actual vehicle operating condition of the target vehicle is determined, and the target vehicle is controlled to drive according to the actual torque value.

5. The fault diagnosis method as described in claim 4, characterized in that, After the step of determining the actual torque value corresponding to the actual vehicle operating condition of the target vehicle and controlling the target vehicle to drive according to the actual torque value if the target vehicle is in a reverse towing state, the method further includes: Update the cumulative count of the target vehicle's resumed driving after being towed, and check whether the updated cumulative count of resumed driving is greater than a third preset threshold; If the updated cumulative count of resumed driving is greater than the third preset threshold, the target vehicle is controlled to drive according to the preset torque simulation value until the target driving cycle ends.

6. The fault diagnosis method according to any one of claims 1 to 5, characterized in that, The fault diagnosis method further includes: If the secondary voltage is greater than the upper limit of the preset range, then the fault type of the ignition system is determined to be an ignition coil fault. If the secondary voltage is less than the lower limit of the preset range, the fault type of the ignition system is determined to be a misfire fault.

7. A fault diagnosis device, characterized in that, The fault diagnosis device includes a memory and a processor. The memory stores a fault diagnosis program that can run on the processor. When the fault diagnosis program is executed by the processor, it implements the steps of the fault diagnosis method as described in any one of claims 1 to 6.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a fault diagnosis program, which, when executed by a processor, implements the steps of the fault diagnosis method as described in any one of claims 1 to 6.

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