Method for diagnosing faults in a vehicle, and diagnostic device for a vehicle

Abstract

Examples relate to a method (10) for diagnosing faults in a vehicle, the method (10) comprising: acquiring (11) a fault message concerning a first vehicle component; analyzing (12) an operative relationship between the first vehicle component and at least one further vehicle element; acquiring (13) a fault message concerning a second vehicle component; analyzing (14) an operative relationship between the second vehicle component and at least one further vehicle element; and in the event that the further vehicle element operatively related to the first vehicle component and the further vehicle element operatively related to the second vehicle component are identical: outputting (15) an indication of a potential fault with the further vehicle element. Further examples relate to a diagnostic device for diagnosing a vehicle.

Description

[0001] 24-2851

[0002] METHOD FOR FAULT DIAGNOSTIC IN A VEHICLE AND DIAGNOSTIC DEVICE FOR A VEHICLE

[0003] Technical field

[0004] Exemplary embodiments relate to a method for fault diagnosis in a vehicle, particularly for vehicles with at least two, and especially multiple, fault messages. Further exemplary embodiments relate to a method for fault diagnosis of vehicles of different vehicle types. A computer program for executing the proposed methods is also provided. Additionally, a diagnostic device for diagnosing a vehicle is proposed.

[0005] background

[0006] Modern vehicles are equipped with numerous functions that enable continuous self-diagnosis. For example, it is essential to ensure that safety-relevant components are always functioning correctly. This can be achieved, for instance, by querying or testing the components via the vehicle's communication bus.

[0007] The more components capable of performing their own diagnostics are installed, the more frequently false error messages can occur, for example, when the component displaying the error message is actually fully functional and the real fault lies elsewhere. This can lead to unnecessary repair costs that could be avoided. In some cases, a false error message from a discrete component can point to a different fault in the vehicle. However, the actual fault cannot be identified based on the discrete error message.

[0008] From DE 102012 106 077 A1, a diagnostic device for a motor vehicle is known. This device is used to control the communication between a host system and control units.24-2851

[0009] a device integrated into the vehicle electrical system of a motor vehicle, comprising the following features: a diagnostic interface, in particular an on-board diagnostics (OBD) interface, for communication with the control units; a WLAN interface for communication with the host system; a WLAN module for controlling data transmission between the device and the host system via the WLAN interface; a diagnostic module for processing data for communication with the host system; and a vehicle communication module for controlling communication between the diagnostic module and the control units, wherein the WLAN module and the diagnostic module are implemented in a common WLAN processor and the vehicle communication module is implemented in a separate vehicle communication processor with a real-time capable operating system.

[0010] There are diagnostic tools that offer comprehensive diagnostics for all control units, as well as the ability to perform tests for various vehicles and diverse service functions. This includes reading fault codes and reading and saving data streams. Automatic diagnostic reports can be generated. During tests, certain diagnostic tools send specific commands to the selected component, thereby controlling its function and enabling a reliable check of the component's operating status.

[0011] This allows error messages from individual vehicle components to be recorded and displayed. A displayed error message can lead to the replacement of the affected component. However, this is only useful if there is actually a fault with that component.

[0012] Summary

[0013] One of the purposes of this disclosure is to provide improved concepts for vehicle diagnostics, in particular to detect when fault messages are issued by functioning components and, in this case, to provide an indication of an actual cause of the fault.

[0014] This problem is solved according to the subject matter of the independent claims. Further advantageous embodiments are described in the dependent claims, the following description, and in conjunction with the figures. 24-2851

[0015] Accordingly, a procedure for fault diagnosis in a vehicle is proposed. The procedure comprises the following steps: recording a fault message (e.g., first fault message) from a first vehicle component and analyzing the interaction between the first vehicle component and at least one other vehicle element. Then, recording a fault message (e.g., second fault message) from a second vehicle component and analyzing the interaction between the second vehicle component and at least one other vehicle element. It is possible that the other vehicle elements interacting with the vehicle components are identical; in other words, the other vehicle element can interact with both the first and the second vehicle component.In the event that the further vehicle element, which is related to the first vehicle component, and the further vehicle element, which is related to the second vehicle component, are identical, a warning about a potential fault of the further vehicle element is issued according to the procedure.

[0016] Vehicle components can be discrete parts, such as control units, actuators, or sensors. For example, a vehicle component could be an actuator with a motor or motion unit, a lidar or radar unit, a water pump, or an airbag system. The other vehicle element can be a similar discrete part that interacts with or is connected to the vehicle component. Alternatively, the other vehicle element can be a unit distributed throughout the vehicle (e.g., a group of several active and / or passive components, as is the case in the vehicle electrical system or communication buses) that interacts with several parts of the vehicle electrical system, such as parts of the electrical system (e.g., the electrical system control unit, wiring harness, or power supply).

[0017] The proposed method advantageously utilizes existing discrete error messages from individual components and establishes a potential relationship between them. A number of different vehicle components are connected (e.g., via physical connections; e.g., functional connections through data exchange or power supply) to other vehicle elements, for example, for communication or data transmission, or for power supply. The other vehicle element could, for example, be part of the vehicle's electrical system or a specific section of a zonal electrical system. If the first vehicle component and the second vehicle component are now interconnected within this section of the electrical system,24-2851

[0018] The vehicle elements that are connected to the two vehicle components are identical, namely the corresponding part of the vehicle electrical system.

[0019] Advantageously, the method uses statistical values ​​to evaluate the error messages from two or more vehicle components. For example, if there is no connection between the two vehicle components and they fail simultaneously or in very close temporal proximity, it may be statistically very unlikely that the vehicle component itself has an actual fault. Rather, in such a situation, it can be statistically assumed that the fault lies elsewhere. If both vehicle components are operatively related to the other vehicle element they share, there is a probability that the other vehicle element has an actual fault. For example, this allows a potential fault to be found in vehicle elements that do not have their own discrete self-diagnostics and fault output.Frequent or simultaneous error messages from independent components in a vehicle can be better evaluated.

[0020] It is possible that a vehicle component may generate an error message due to a fault in another vehicle component, even though the vehicle component itself is functioning correctly (e.g., an error message due to faulty communication in the vehicle electrical system caused by a fault in the electrical system). Alternatively, a malfunction in the other vehicle component may cause an actual fault in the vehicle component (e.g., an overvoltage in the electrical system that can lead to a defect in the vehicle component). In both cases, this method can advantageously draw attention to a potential fault in the other vehicle component, since simply replacing the vehicle component would not constitute an effective repair measure; rather, the same fault would likely reappear with a new vehicle component.

[0021] The proposed method can therefore, through improved diagnostic capabilities, enable more effective fault diagnosis and thus repair of a vehicle with fault messages from discrete vehicle components. In particular, it is possible to detect vehicle faults that are cross-component and therefore cause fault entries in the fault memory of independent vehicle components.24-2851

[0022] According to one example, the recording of the fault message from the first vehicle component and the fault message from the second vehicle component are intended to occur in a single recording process (e.g., simultaneously during a diagnostic procedure or immediately one after the other, e.g., during a workshop visit) or within a predetermined maximum time period (e.g., within one week, one month, or two months; e.g., depending on the statistical failure probabilities of the first and second vehicle components, whereby the maximum time period may be longer if the failure probabilities of the vehicle components are lower). Expressed in another metric, the recording of at least two fault messages can occur within a predetermined maximum driving distance.As an alternative to a temporal correlation, a distance traveled is a further or additional criterion for a correlation or proximity between independent error messages. This temporal or distance-based limitation allows for the selection of a statistical threshold within which independently occurring errors are unrealistic, and outside of which even independently developed vehicle components can realistically exhibit an actual fault (e.g., the occurrence of independent error messages over a period of more than one year or after a mileage of more than 50,000 km).

[0023] As an example, the predetermined maximum time period is set to be longer if more than two error messages from different vehicle components are recorded. For instance, a maximum time period of two months can be used as a statistical threshold for two error messages, but a maximum time period of three months can be used if three or more vehicle components independently issue error messages. When multiple vehicle components independently issue error messages, even with longer time periods, it is unlikely that all of these components have actual faults or faults caused by the component itself. Rather, a common, underlying source of error for the error messages is more probable.

[0024] According to one example, the first and second vehicle components are designed independently of each other. For example, there is no physical or functional connection.-24-2851

[0025] There is no direct connection between the vehicle components; for example, there is no direct communication between the two vehicle components. For instance, these are vehicle components with different functions.

[0026] According to one example, the recording of error messages from both components is intended to take place within a predetermined period after completion of the initial assembly of the vehicle. For example, the procedure can enable effective diagnosis of an actually faulty vehicle component if two (or more) independent faults occur in new cars within less than, for example, two months (or less than three months or less than six months).

[0027] Another aspect concerns a procedure for fault diagnosis in a vehicle from the first production series. This procedure comprises the steps of recording a fault message from a vehicle component of the first production series and checking a number of fault messages related to that component within the first production series (e.g., failure rate or error rate). This checking can be done, for example, by recording further fault messages from vehicles in the first production series concerning that component. In particular, clusters of fault messages for a component in a first vehicle type can be identified. For example, relevant information can be retrieved from the vehicle manufacturer's backend or provided by the vehicle manufacturer. Thus, the number of fault messages for the component in the first production series can be available, for example, as a percentage.

[0028] The procedure involves comparing the number of error messages related to the vehicle component within the first vehicle series with the number of error messages related to the same vehicle component within a second vehicle series. Alternatively, the failure rate of the vehicle component in the first vehicle series can be compared with a calculated failure value for the vehicle component (e.g., statistically expected failure of the vehicle component depending on the component's age or operating time). It is possible that the same vehicle component causes a significantly lower number of error messages in the second vehicle series than in the first. "Significantly lower" could mean, for example, less than 80%, less than 70%, less than 60%, or less than 50% of the error rate.24-2851

[0029] For example, the vehicle component with the error message might have a failure rate of 1% in the first vehicle batch, but only a failure rate of 0.2% in the second batch. In such a case, the following procedure can be performed: an analysis of the interaction between the vehicle component of the vehicle in the first batch and at least one other vehicle component of the same vehicle, and an indication of a potential failure of the other vehicle component.

[0030] The proposed method, based on fleet diagnostics, allows for a comparison of the frequency of error messages from the same component used in different vehicle series. If the second vehicle series generates hardly any error messages from the same component used in the first, but the first series experiences frequent error messages from this component, it is likely that the actual or underlying fault lies elsewhere, for example, in another vehicle component.

[0031] For example, the interaction between a vehicle component and another vehicle element involves a communication link. For instance, the vehicle component might output an error message due to faulty communication with the other vehicle element. In a state-of-the-art diagnostic procedure, this would then indicate that the vehicle component is defective, even though the fault could lie, for example, in the communication channel. Advantageously, such a deeper underlying cause can be identified using this procedure.

[0032] According to one example, the interaction between the vehicle component and the other vehicle element involves an operating voltage. For instance, the voltage level of the vehicle electrical system can fluctuate, so that an unreliable input voltage at the vehicle component can lead to a fault code for the vehicle component. Here, too, a state-of-the-art diagnostic procedure would indicate that the discrete vehicle component is defective, even though the fault could lie, for example, with the voltage source or a problem in the vehicle electrical system. Advantageously, this procedure can identify that the actual fault is potentially not in the vehicle component itself, thus avoiding unnecessary and ineffective replacement work on the vehicle component.24-2851

[0033] According to one example, the analysis of the causal relationships is envisaged to be carried out using artificial intelligence. Detecting the potential fault in the other vehicle component may require, in particular, a comprehensive comparison of various constellations of causal relationships and functionalities of discrete components, or pattern matching. Advantageously, when using AI, this can be done particularly efficiently even with large datasets, and causal relationships that are not easily recognizable manually can be identified more easily.

[0034] Another aspect concerns a computer program product or non-volatile storage medium containing program code to execute the procedure described above or below, when the computer program or program code is run on a processor, computer, or programmable hardware. Such a program can advantageously be run on a test computer, diagnostic device, or alternatively, a backend (e.g., a server connected to the vehicle or a cloud service) to execute the proposed procedure and perform the improved diagnostic procedure. This allows for the detection of error messages that occur in a (e.g., temporally) correlated manner but are statistically improbable. In this case, using the computer program can provide an indication of a more likely, underlying source of the error.

[0035] Another aspect concerns a diagnostic device for diagnosing a vehicle, wherein the diagnostic device is configured to perform a procedure described previously or subsequently. For example, the previously described computer program product may be provided on the diagnostic device. This makes the described, improved vehicle diagnostics available, for example, on a mobile diagnostic device.

[0036] Character description

[0037] Examples of implementation are explained in more detail below with reference to the accompanying figures. These show:

[0038] Fig. 1 shows a flowchart of a procedure for fault diagnosis in a vehicle with at least two temporally correlated fault messages; and24-2851

[0039] Fig. 2 shows a flowchart of a procedure for fault diagnosis in a vehicle of a first vehicle series.

[0040] Description

[0041] Several embodiments are now described in more detail with reference to the accompanying drawings, which illustrate some of these embodiments. For clarity, the thickness dimensions of lines, layers, and / or regions may be exaggerated in the figures. In the following description of the accompanying figures, which only show some exemplary embodiments, the same reference numerals may denote identical or comparable components.

[0042] An element described as "connected" or "coupled" to another element may be directly connected or coupled to that other element, or interposed elements may be present. Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meanings that a person skilled in the art in the field to which the embodiments belong would associate with them.

[0043] Figure 1 shows a flowchart of a procedure 10 for fault diagnosis in a vehicle. The procedure 10 comprises the following steps: acquiring 11 a fault message from a first vehicle component and analyzing 12 the interaction of the first vehicle component with at least one other vehicle element; and acquiring 13 a fault message from a second vehicle component and analyzing 14 the interaction of the second vehicle component with at least one other vehicle element. The procedure 10 further comprises, in the case that the other vehicle element interacting with the first vehicle component and the other vehicle element interacting with the second vehicle component are identical: outputting 15 a notification of a potential fault in the other vehicle element.

[0044] Method 10 can be applied, for example, in a diagnostic device or on a service computer (e.g., cloud-based). This allows the (e.g., temporal) relationship between several independent error messages to be identified and advantageously24-2851

[0045] A causal source of the error messages (e.g., a fault located behind the vehicle component or deeper down) can be identified. For example, using procedure 10 can prevent the replacement of functional vehicle components simply because they are issuing an error message, when the actual fault is caused by a different vehicle component.

[0046] Fig. 2 shows a flowchart of a procedure 20 for fault diagnosis in a vehicle of a first vehicle series. The procedure comprises the steps: acquiring 21 a fault message of a vehicle component of the vehicle of the first vehicle series, checking 22 a number of fault messages relating to the vehicle component within the first vehicle series, and comparing 23 the number of fault messages relating to the vehicle component within the first vehicle series with a number of fault messages relating to the same vehicle component within a second vehicle series.The procedure 10 further includes, in the case that the same vehicle component causes a significantly lower number of error messages in the second vehicle series than in the first vehicle series: an analysis 24 of an interaction between the vehicle component of the vehicle of the first vehicle series and at least one other vehicle element of the vehicle and an output 25 of an indication of a potential error of the other vehicle element.

[0047] Method 20 can, for example, make it possible to recognize, based on statistical observations, that a vehicle component that is issuing an error message may not actually be faulty. For example, the same vehicle component may function very reliably in the second vehicle series. In this case, method 20 can indicate that the actual fault might be more deeply rooted, and through analysis 24 of the interaction with the other vehicle element, an indication 25 can be issued that the other vehicle element could indeed be the actual source of the fault.

[0048] Further details and aspects are mentioned in connection with the embodiments described above or below. The embodiment shown in Fig. 2 may have one or more optional additional features corresponding to one or more aspects mentioned in connection with the proposed concept or with one or more embodiments described above (e.g., Fig. 1) or below. 24-2851

[0049] Examples refer to a diagnostic function for detecting overarching vehicle problems, e.g., in the case that a faulty vehicle element leads to an error output in various, independent vehicle components.

[0050] Other approaches focus exclusively on diagnosing individual components and not on problems caused by overarching systems. For example, a problem that occurs in the overarching LIN communication, in other communication buses, or with the vehicle electrical system voltage, and which can cause problems in various systems or components, will not be diagnosed using other diagnostic tools.

[0051] This can lead to vehicles having numerous workshop visits without the actual problem being identified. However, closer analysis of such vehicles can reveal that the issue is not isolated problems with various components, but rather a more widespread problem, for example, in the vehicle's electrical system (e.g., regarding the supply voltage to components or faulty or disrupted communication processes). If, for example, a fault is reported for independently functioning components (e.g., the electric water pump and the air flap control) almost simultaneously shortly after a vehicle is delivered, the probability of both components failing at the same time is statistically very low. For instance, both components could be issuing error messages because something is wrong with the communication link to a central control unit.If such a broader or deeper-seated problem is not identified, both components, for example, will be replaced unnecessarily, and the vehicle's actual problem will persist. Effective troubleshooting cannot occur.

[0052] Upon closer inspection, the workshop test device (e.g., the diagnostic device proposed here) could have already provided a corresponding indication during a first workshop visit (e.g., an initial vehicle diagnosis), since two independently operating electronic components reported a fault simultaneously or almost simultaneously, which is sufficiently improbable to assume that a deeper problem must be present.

[0053] The output of such a notice (e.g., indirect cause of an error message issued by a component; e.g., underlying cause of the error) is carried out according to the concepts of DIN 24-2851.

[0054] This disclosure enables, for example, the implementation of a service tester function that specifically searches for error memory entries that occurred simultaneously or very close to one another, particularly in independently operating systems, and can then specifically point to a more widespread problem. This can be achieved by searching for a causal relationship between at least two components that output an error message and another common vehicle element that may be the cause of the error messages.

[0055] This disclosure provides concepts that can enable a sound and effective diagnosis of error messages from vehicle components. In particular, when error messages occur independently, underlying problem sources can be diagnosed and corresponding indications of potentially defective vehicle components can be provided.

Claims

24-2851 Patent claims 1. Method (10) for fault diagnosis in a vehicle, the method comprising: (11) Capturing an error message from a first vehicle component; Analyzing (12) a causal relationship between the first vehicle component and at least one other vehicle element; (13) Receiving an error message from a second vehicle component; Analyzing (14) a causal relationship between the second vehicle component and at least one other vehicle element; and In the event that the further vehicle element that is related to the first vehicle component and the further vehicle element that is related to the second vehicle component are identical: Issue (15) a warning about a potential fault in the other vehicle element.

2. Method (10) according to claim 1, wherein the acquisition (11) of the fault message of the first vehicle component and the acquisition (13) of the fault message of the second vehicle component take place in a common acquisition process or within a predetermined maximum time period or within a predetermined maximum driving distance of the vehicle.

3. Method (10) according to claim 2, where the predetermined maximum time duration is increased if more than two error messages from different vehicle components are detected (11, 13).

4. Method (10) according to any one of claims 1 to 3, where the first and second vehicle components are designed independently of each other. 24-2851 5. Method (10) according to any one of the preceding claims, wherein the recording (11, 13) of the error messages of both components takes place within a predetermined period after completion of the initial assembly of the vehicle.

6. Method (20) for fault diagnosis in a vehicle of a first series of vehicles, the method comprising: - Recording (21) a fault message from a vehicle component of the first series vehicle; Check (22) a number of error messages relating to the vehicle component within the first vehicle series; (23) comparing the number of error messages relating to the vehicle component within the first vehicle series with the number of error messages relating to the same vehicle component within a second vehicle series; and In the event that the same vehicle component causes a significantly lower number of error messages in the second vehicle series than in the first vehicle series: Analyze (24) a causal relationship between the vehicle component of the vehicle of the first vehicle series and at least one other vehicle element of the vehicle; and Issue (25) a warning of a potential fault in the other vehicle element.

7. Method (10, 20) according to one of the preceding claims, where the interaction between the vehicle component and the other vehicle element concerns a communication link and / or an operating voltage.

8. Method (10, 20) according to one of the preceding claims, where the analysis (12, 14, 24) of the causal relationship is carried out using artificial intelligence. 24-2851 9. Computer program product or non-volatile storage medium containing program code for performing the method (10, 20) according to any one of the preceding claims when the program code is executed on a processor, a computer, or programmable hardware.

10. Diagnostic device for diagnosing a vehicle, wherein the diagnostic device is configured to perform a method (10, 20) according to one of claims 1 to 8.

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