An OBD diagnostic method and system based on instrument

Abstract

The present invention belongs to the field of vehicle diagnosis technology, and in particular, relates to an OBD diagnostic method and system based on an instrument, wherein the method includes: connecting the instrument with a diagnostic device through an OBD diagnostic interface in a bus communication mode, and connecting the instrument with other electronic control units of the vehicle through multiple communication modes (bus or non-bus); after the instrument receives a diagnostic request initiated by the diagnostic device, it obtains diagnostic response data through communication with other electronic control units, and converts these data into response data packets consistent with the diagnostic device request protocol, and then returns them to the diagnostic device; the diagnostic device runs a fault identification operation according to the received response data packet and generates a diagnostic operation result. By connecting the instrument to all electronic control units of the vehicle, the present invention can solve the problem of realizing OBD diagnosis when the vehicle itself does not have bus OBD diagnostic capabilities.

Description

Technical Field

[0001] The present invention belongs to the technical field of vehicle diagnosis, and in particular relates to an instrument-based OBD diagnosis method and system. Background Art

[0002] OBD diagnosis is also called the vehicle automatic diagnosis system. This system mainly monitors the vehicle's exhaust gas exceeding the standard or the system failing at any time based on the engine's operating status. It will issue a warning when the standard is exceeded and the fault light will light up when the system fails. At the same time, the control module will store the fault information in the memory and export the fault code from the control module through a certain procedure. Maintenance personnel can quickly and accurately determine the nature and location of the fault based on the fault code.

[0003] The existing OBD diagnostic system includes an OBD diagnostic interface, which is connected to each electronic control unit (ECU) of the vehicle through the OBD diagnostic interface. When a fault occurs in the vehicle, the parameters of the ECU are read to diagnose the fault of the ECU. However, the OBD diagnostic interface includes sixteen bus interfaces, and there are nine bus interface protocols that have been developed. These nine interfaces have fixed communication protocols, and there is a fixed corresponding relationship between the connection between the electronic control unit and the OBD diagnostic interface. When performing fault diagnosis, due to the limitation of the communication protocol, diagnosis is often inconvenient. For example, the OBD diagnostic protocols used by vehicles on the market currently include diagnostic protocols such as ISO15765 and SAEJ1939. Most OBD diagnostic devices on the market only have good support for ISO15765, and have incomplete or no support for other diagnostic protocols such as SAEJ1939. In addition, there are electronic control units that are not suitable for ISO15765. Therefore, it is often the case that a certain electronic control unit of the vehicle cannot realize OBD diagnosis because it does not have the bus OBD diagnostic capability. It is necessary to develop a new bus interface, which is costly. Summary of the invention

[0004] The technical problem solved by the present invention is to provide an instrument-based OBD diagnostic method and system to solve the problem of communication protocol limitations in the existing OBD diagnostic technology.

[0005] The present invention provides a basic solution 1: an OBD diagnostic method based on an instrument, comprising:

[0006] The instrument and the diagnostic equipment are connected in a bus communication mode through the OBD diagnostic interface, and the instrument and the vehicle electronic control unit are connected through a bus or non-bus;

[0007] The diagnostic device initiates a diagnostic request to the instrument through the OBD diagnostic interface, and the instrument obtains diagnostic response data from the electronic control unit after receiving the diagnostic request;

[0008] The instrument converts the acquired diagnostic response data into a return response data packet consistent with the diagnostic device request protocol and returns it to the diagnostic device;

[0009] The diagnostic device runs a fault identification job according to the returned response data packet and generates a diagnostic job result.

[0010] The principle and advantage of the basic scheme 1 provided by the present invention are: in the existing related technology, the diagnostic equipment is connected to the OBD diagnostic interface of the vehicle to read the parameters of the electronic control unit to identify the fault. The communication protocol is fixed and the diagnosis is restricted by the communication protocol, which makes the diagnosis inconvenient. It is often the case that a certain electronic control unit of the vehicle cannot realize OBD diagnosis because it does not have the bus OBD diagnostic capability, and a new bus interface needs to be developed, which is costly.

[0011] Therefore, in order to solve the related problems in the prior art, the instrument is first connected to the diagnostic device through the OBD diagnostic interface in a certain bus communication mode, and the instrument is connected to other electronic control units of the vehicle through multiple communication modes (bus or non-bus); after the instrument receives the diagnostic request initiated by the diagnostic device, it obtains the diagnostic response data through the communication mode with other electronic control units, and converts the data into a response data packet consistent with the request protocol of the diagnostic device, and then returns it to the diagnostic device; the diagnostic device runs the fault identification operation according to the received response data packet and generates the diagnostic operation result; in addition, the instrument, as a necessary device for the vehicle itself, is itself connected to some electronic control units in the vehicle and has the function of displaying the faults of some electronic control units.

[0012] Therefore, the advantages of the present invention are: (1) the various electronic control units in the vehicle are connected through the instrument, and the instrument and the diagnostic device can be connected to the same bus interface through the OBD diagnostic interface, so that the service diagnostic request protocol of the diagnostic device is converted into the same as the service diagnostic protocol of the electronic control unit, thereby solving the problem of communication limitations in the OBD diagnostic technology; (2) the communication limitations in the vehicle's OBD diagnostic technology are solved through the instrument. The instrument is an essential device for the vehicle. On the one hand, it is also connected to other electronic control units and has the function of displaying the faults of some electronic control units; on the other hand, it does not need to install additional adapters or adapter devices, has strong applicability, and saves installation costs; (3) the instrument and the OBD diagnostic interface are both located at the front end of the vehicle and are easy to use; (4) the instrument itself is connected to other electronic control units in the vehicle, and then the instrument is connected to other electronic control units in the vehicle to provide OBD diagnostic functions for other electronic control units that do not have OBD diagnostic functions, thereby providing a low-cost OBD diagnostic interface proxy function.

[0013] Furthermore, the diagnostic response data includes real-time fault data, historical fault data and fault freeze frame data.

[0014] Beneficial effects: Real-time fault data is a period of data collected by the instrument when the electronic control unit goes from no fault to fault. Historical fault data is the data when the electronic control unit has historical faults, which is used as a reference for this fault diagnosis. Fault freeze frame data is frame data frozen when a fault occurs in the electronic control unit. The frame data contains information such as the cause of the fault.

[0015] Furthermore, the diagnostic device initiates a diagnostic request to the instrument through the OBD diagnostic interface, and the instrument obtains diagnostic response data from the electronic control unit after receiving the diagnostic request, and further includes:

[0016] The instrument runs a fault identification job based on the read diagnostic response data and generates an instrument job result.

[0017] Beneficial effects: As an essential device for the vehicle itself, the instrument has stronger computing and storage capabilities than the electronic control unit, and can perform fault diagnosis functions without diagnostic equipment. In addition, the instrument can store a certain amount of electronic control unit diagnostic history data, which is conducive to discovering the fault generation process and facilitating finding the cause of the fault.

[0018] Furthermore, it also includes:

[0019] Feedback instrument operation results and diagnostic operation results to the user end to obtain user solutions and fault resolution results;

[0020] The instrument performs a second fault identification operation and generates a second instrument operation result. If the fault is resolved in the second instrument operation result, a fault log record is generated.

[0021] Beneficial effects: The user end can be used to make solutions based on the diagnosis results. At the same time, the computing power of the instrument itself can provide verification functions when the user solves the problem. After the fault problem is solved, the instrument can also generate a fault log record, which can be used as historical fault data.

[0022] The second basic scheme provided by the present invention is: an OBD diagnostic system based on an instrument, comprising an instrument, an OBD diagnostic interface and a diagnostic device, wherein the instrument and the diagnostic device are communicatively connected in a bus manner through the OBD diagnostic interface, the instrument is connected to the vehicle electronic control unit through a bus or a non-bus, the diagnostic device is used to send a diagnostic request protocol to the instrument through the OBD diagnostic interface, the instrument comprises a data acquisition module, a protocol conversion module, a transmission module and a control module, the data acquisition module, the protocol conversion module and the transmission module are all electrically connected to the controller, the data acquisition module is used to obtain diagnostic response data from the electronic control unit after receiving the diagnostic request, the protocol conversion module is used to convert the acquired diagnostic response data into a return response data packet consistent with the diagnostic device request protocol, the control module is used to control the transmission module to transmit the return response data packet to the diagnostic device; the diagnostic device is also used to run a fault identification operation according to the return response data packet to generate a diagnostic operation result.

[0023] The principles and advantages of the basic scheme 2 provided by the present invention are as follows: In the existing related technologies, the diagnostic equipment is connected to the OBD diagnostic interface of the vehicle to read the parameters of the electronic control unit to identify faults. The communication protocol is fixed and the diagnosis is restricted by the communication protocol, which makes the diagnosis inconvenient. It is often the case that a certain electronic control unit of the vehicle cannot perform OBD diagnosis because it does not have the bus OBD diagnostic capability, and a new bus interface needs to be developed, which is costly.

[0024] Therefore, in order to solve the related problems in the prior art, the instrument is first connected to the diagnostic device through the OBD diagnostic interface in a certain bus communication mode, and the instrument is connected to other electronic control units of the vehicle through multiple communication modes (bus or non-bus); after the instrument receives the diagnostic request initiated by the diagnostic device, it obtains the diagnostic response data of other electronic control units through the data acquisition module, and converts these data into response data packets consistent with the request protocol of the diagnostic device through the protocol conversion module, and then controls the transmission module through the control module to return them to the diagnostic device; the diagnostic device runs the fault identification operation according to the received response data packet and generates the diagnostic operation result; in addition, the instrument, as a necessary device for the vehicle itself, is itself connected to some electronic control units in the vehicle and has the function of displaying the faults of some electronic control units.

[0025] Therefore, the advantages of the present invention are: (1) the various electronic control units in the vehicle are connected through the instrument, and the instrument and the diagnostic device can be connected to the same bus interface through the OBD diagnostic interface, so that the service diagnostic request protocol of the diagnostic device is converted into the same as the service diagnostic protocol of the electronic control unit, thereby solving the problem of communication limitations in the OBD diagnostic technology; 2) the communication limitations in the vehicle's OBD diagnostic technology are solved through the instrument. The instrument is an essential device for the vehicle. On the one hand, it is also connected to other electronic control units and has the function of displaying the faults of some electronic control units; on the other hand, it does not require the installation of additional adapters or adapter devices, has strong applicability, and saves installation costs; (3) the instrument and the OBD diagnostic interface are both located at the front end of the vehicle and are easy to use; (4) the instrument itself is connected to other electronic control units in the vehicle, and then the instrument is connected to other electronic control units in the vehicle to provide OBD diagnostic functions for other electronic control units that do not have OBD diagnostic functions, thereby providing a low-cost OBD diagnostic interface proxy function.

[0026] Furthermore, the diagnostic response data includes real-time fault data, historical fault data and fault freeze frame data.

[0027] Beneficial effects: Real-time fault data is a period of data collected by the instrument when the electronic control unit goes from no fault to fault. Historical fault data is the data when the electronic control unit has historical faults, which is used as a reference for this fault diagnosis. Fault freeze frame data is frame data frozen when a fault occurs in the electronic control unit. The frame data contains information such as the cause of the fault.

[0028] Furthermore, the instrument further includes a fault identification module, which is electrically connected to the control module and is used to run a fault identification operation according to the acquired diagnostic response data and generate an instrument operation result.

[0029] Beneficial effects: As an essential device for the vehicle itself, the instrument has stronger computing and storage capabilities than the electronic control unit. Through the fault identification module, the fault diagnosis function can be performed without diagnostic equipment. The instrument can not only display the fault diagnosis results, but also display the manufacturer's troubleshooting methods and recommended solutions when the fault occurs based on the fault diagnosis results. In addition, the diagnostic results of the instrument can be compared with the diagnostic results of the diagnostic equipment, which is conducive to analyzing the differences in the diagnostic results and finding the cause of the fault.

[0030] Furthermore, it also includes a user end, which is communicatively connected to the instrument and the diagnostic device. The instrument also includes a recording module. The user end is used to receive instrument operation results and diagnostic operation results, and generate user solutions. The fault identification module is also used to run the fault identification operation for a second time after the fault is resolved, and generate a secondary instrument operation result. If the fault has been resolved in the secondary instrument operation result, the recording module generates a fault log record.

[0031] Beneficial effects: The user end can be used by the user to make solutions based on the diagnosis results. At the same time, the fault identification module of the instrument can provide verification function when the user solves the problem. After the fault problem is solved, the recording module in the instrument can also generate a fault log record, which can be used as historical fault data. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a flowchart of an embodiment of the present invention;

[0033] Figure 2 is a principle block diagram of an embodiment of the present invention;

[0034] Figure 3 is a flowchart of the implementation process of an embodiment of the present invention;

[0035] Figure 4 This is a principle block diagram of Example 1 in an embodiment of the present invention;

[0036] Figure 5 This is a flowchart of an implementation process of Example 1 in an embodiment of the present invention;

[0037] Figure 6 This is a principle block diagram of Example 2 in an embodiment of the present invention;

[0038] Figure 7 This is a flowchart of the implementation process of Example 2 in the embodiment of the present invention;

[0039] Figure 8 1 is a principle block diagram of an instrument system in an embodiment of the present invention. DETAILED DESCRIPTION

[0040] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. At the same time, although a logical order is shown in the embodiments, in some cases, the steps shown or described may be performed in an order different from that shown herein.

[0041] The following is further described in detail through specific implementation methods:

[0042] The embodiment is basically as follows Figure 1 , Figure 2 and Figure 3As shown: An OBD diagnostic method based on instrumentation, comprising:

[0043] Step 1: The instrument and the diagnostic device are connected in a bus communication manner through the OBD diagnostic interface, and the instrument and the vehicle electronic control unit are connected through a bus or non-bus.

[0044] In this embodiment, the instrument is connected to the vehicle's OBD diagnostic interface through communication methods including but not limited to CAN bus, Klinezon, Ethernet, etc. The diagnostic device and the OBD diagnostic interface are connected through an established diagnostic protocol, such as the diagnostic protocol of the CAN bus. At the same time, in this embodiment, the instrument is connected to the vehicle's engine, motor, gearbox, BMS and other electronic control units that require OBD diagnosis through a bus connection to obtain information such as the status and value of each electronic control unit.

[0045] Step 2: The diagnostic device initiates a diagnostic request to the instrument through the OBD diagnostic interface. After receiving the diagnostic request, the instrument obtains diagnostic response data from the electronic control unit.

[0046] The diagnostic response data includes real-time fault data, historical fault data and fault freeze frame data.

[0047] Step 3: The instrument converts the acquired diagnostic response data into a return response data packet consistent with the diagnostic device request protocol and returns it to the diagnostic device.

[0048] In this embodiment, the diagnostic device sends a diagnostic request protocol to the instrument through the OBD diagnostic interface, such as Figure 4 and Figure 5 Example 1 shown: the diagnostic device reads the current DTC (service diagnostic request) fault code of the engine. The diagnostic device is connected to the OBD diagnostic interface through the CAN bus, and the instrument is also connected to the OBD diagnostic interface through the CAN bus. At the same time, the instrument is also connected to the engine ECU through the Kline bus. The diagnostic device initiates a service diagnostic request based on ISO15031 through CAN, where the engine ECU diagnostic request address is mapped to 0x700 on the OBD, and the response address is 0x708. After receiving the diagnostic request, the instrument initiates a request to establish communication based on ISO14230 to the engine ECU through Kline; after the communication between the instrument and the engine ECU is successfully established, that is, after the unlocking is successful, the instrument initiates a service request based on ISO14230 to the engine ECU, where the physical address of the engine ECU is 0x80. The instrument obtains the diagnostic response data of the engine ECU, parses and converts it into the ISO15031 return diagnostic response data transmitted back to the diagnostic device, and finally the instrument sends the converted return diagnostic response data of the engine ECU back to the diagnostic instrument through the CAN bus.

[0049] In the above embodiment, examples of protocol conversion and transmission through Kline are listed. In order to reflect multi-protocol conversion, other embodiments of this embodiment also include: Figure 6 and Figure 7 Example 2 shown: the diagnostic device reads the current speed of the motor, and initiates a service diagnostic request based on ISO14229 through the CAN bus, where the motor diagnostic request address is mapped to 0x710 on the OBD, and the response address is 0x718; after receiving the diagnostic request, the instrument captures the frequency signal emitted by the motor through the PWM waveform; after obtaining the motor frequency signal, the instrument parses and converts it into the motor speed, and then converts it into ISO14229 return diagnostic response data to be returned to the diagnostic device, and finally the instrument sends the converted ISO14229 return diagnostic response data back to the diagnostic device through the CAN bus.

[0050] In the above two examples, the diagnostic response data obtained by the instrument includes real-time fault data, historical fault data and fault freeze frame data, wherein the real-time fault data is a period of data collected by the instrument when the electronic control unit changes from no fault to fault, the historical fault data is the data when the electronic control unit has a fault in the past, which is used as a reference for this fault diagnosis, and the fault freeze frame data is the frame data frozen when a fault occurs in the electronic control unit, and the frame data contains information such as the cause of the fault.

[0051] In step 2, it also includes: the instrument runs a fault identification operation according to the acquired diagnostic response data and generates an instrument operation result.

[0052] In this embodiment, a fault identification module and a storage module are provided in the instrument. The fault identification module is used to identify and analyze the fault code of the received electronic control unit ECU, run the fault identification operation, and thus generate the instrument operation result. The fault identification module enables the instrument to have a strong computing capability, and the generated instrument operation result is stored in the storage module. At the same time, the instrument can be connected to each electronic control unit in the vehicle through a bus. When a certain electronic control unit does not have the OBD diagnostic function, for example, for fault diagnosis of agricultural machinery and equipment, the instrument can be connected to the electronic control unit in the agricultural machinery, thereby transferring the OBD diagnostic interface and the diagnostic equipment, and providing a low-cost OBD diagnostic interface agent function.

[0053] In addition, when the existing diagnostic protocol or diagnostic standard changes, the instrument also includes a wireless communication module. The user can connect to the instrument wirelessly through a mobile terminal to update the firmware or software of the instrument, so that the instrument can be compatible with new standards and protocols. The wireless communication module includes a Bluetooth module, a WIFI module, a 4G module and a 5G module, and in this embodiment it is a Bluetooth module.

[0054] Step 4: The diagnostic device runs a fault identification operation according to the returned packet and generates a diagnostic operation result;

[0055] Step 5: Feedback the instrument operation results and diagnostic operation results to the user end to obtain user solutions and fault resolution results.

[0056] In this embodiment, the diagnostic device receives the return packet transmitted by the instrument, and then reads and analyzes the data in the return packet to generate a diagnostic operation result, and then sends the diagnostic operation result and the instrument diagnostic result to the user end for the user to solve the problem. In addition, the instrument also provides a transmission interface. For example, if the fault problem in the ECU is a software problem, the user rewrites the relevant software in the user end, and then transmits the rewritten software to the corresponding ECU through the transmission interface of the instrument, thereby achieving the purpose of solving the fault problem.

[0057] Step 6: The instrument performs a second fault identification operation to generate a second instrument operation result. If the fault is resolved in the second instrument operation result, a fault log record is generated.

[0058] In this embodiment, the fault identification module in the instrument is also used to provide a verification function when the fault is resolved, that is, the fault identification module of the instrument runs the fault identification operation a second time to verify whether the fault still exists. If the fault is resolved in the verification result, the instrument will generate a fault log record for this fault, which can be used as fault history data and can also facilitate users to view historical fault data.

[0059] In addition, in another technical solution of the present technical solution, an OBD diagnostic system based on an instrument is also included, such as Figure 2 and Figure 8 As shown, the system includes an instrument, an OBD diagnostic interface and a diagnostic device. The instrument and the diagnostic device are communicatively connected in a bus manner through the OBD diagnostic interface. The instrument and the vehicle electronic control unit are connected through a bus or a non-bus. In this embodiment, they are connected through a bus. The diagnostic device is used to send a diagnostic request protocol to the instrument through the OBD diagnostic interface.

[0060] The instrument includes a data acquisition module, a protocol conversion module, a transmission module, a fault diagnosis module and a control module. The data acquisition module, the protocol conversion module, the transmission module and the fault diagnosis module are all electrically connected to the controller. The data acquisition module is used to obtain diagnostic response data from the electronic control unit after receiving a diagnostic request. The protocol conversion module is used to convert the acquired diagnostic response data into a return response data packet consistent with the diagnostic device request protocol. The control module is used to control the transmission module to transmit the return response data packet to the diagnostic device; the fault identification module is used to run a fault identification operation according to the acquired diagnostic response data and generate an instrument operation result; the diagnostic device is also used to run a fault identification operation according to the return response data packet and generate a diagnostic operation result.

[0061] The diagnostic response data includes real-time fault data, historical fault data and fault freeze frame data. The real-time fault data is a period of data collected by the instrument from the time when the electronic control unit has never had a fault to the time when the fault occurs. The historical fault data is the data when the electronic control unit has had a fault in the past, which is used as a reference for this fault diagnosis. The fault freeze frame data is the frame data frozen when a fault occurs in the electronic control unit. The frame data contains information such as the cause of the fault.

[0062] It also includes a user end, which is communicated with the instrument and the diagnostic equipment. The instrument also includes a recording module. The user end is used to receive the instrument operation results and the diagnostic operation results, and generate a user solution. The fault identification module is also used to run the fault identification operation for a second time after the fault is solved, and generate a secondary instrument operation result. If the fault has been solved in the secondary instrument operation result, the recording module generates a fault log record.

[0063] The above are only embodiments of the present invention. Common knowledge such as the known specific structures and characteristics in the scheme is not described in detail here. Ordinary technicians in the relevant field know all the common technical knowledge in the technical field to which the invention belongs before the application date or priority date, can obtain all the existing technologies in the field, and have the ability to apply conventional experimental means before that date. Ordinary technicians in the relevant field can improve and implement this scheme in combination with their own abilities under the enlightenment given by this application. Some typical known structures or known methods should not become obstacles for ordinary technicians in the relevant field to implement this application. It should be pointed out that for those skilled in the art, without departing from the structure of the present invention, several deformations and improvements can be made, which should also be regarded as the scope of protection of the present invention, and these will not affect the effect of the implementation of the present invention and the practicality of the patent. The scope of protection required by this application shall be based on the content of its claims, and the specific implementation methods and other records in the specification can be used to interpret the content of the claims.

Claims

1. An OBD diagnostic method based on an instrument, characterized in that: include: The instrument and the diagnostic device are connected in a bus communication manner through the OBD diagnostic interface, and the instrument and the vehicle electronic control unit are connected through a bus or a non-bus; the electronic control unit includes an electronic control unit with OBD diagnosis and an electronic control unit without OBD diagnosis; The diagnostic device initiates a diagnostic request to the instrument through the OBD diagnostic interface, and the instrument obtains diagnostic response data from the electronic control unit after receiving the diagnostic request; The instrument converts the acquired diagnostic response data into a return response data packet consistent with the diagnostic device request protocol and returns it to the diagnostic device; The diagnostic device runs a fault identification operation according to the returned response data packet and generates a diagnostic operation result; The diagnostic device initiates a diagnostic request to the instrument through the OBD diagnostic interface, and the instrument obtains diagnostic response data from the electronic control unit after receiving the diagnostic request, and further includes: The instrument runs a fault identification operation according to the read diagnostic response data and generates an instrument operation result; It also includes: communicating with the instrument through the mobile terminal to update the instrument firmware or software to be compatible with new standards and protocols; Also includes: Feedback instrument operation results and diagnostic operation results to the user end to obtain user solutions and fault resolution results; The instrument performs a second fault identification operation and generates a second instrument operation result. If the fault is resolved in the second instrument operation result, a fault log record is generated.

2. The OBD diagnostic method based on instrumentation according to claim 1, characterized in that: The diagnostic response data includes real-time fault data, historical fault data and fault freeze frame data.

3. An OBD diagnostic system based on an instrument, characterized in that: The invention comprises an instrument, an OBD diagnostic interface and a diagnostic device, wherein the instrument and the diagnostic device are communicatively connected in a bus manner through the OBD diagnostic interface, the instrument is connected to the vehicle electronic control unit through a bus or a non-bus, the diagnostic device is used to send a diagnostic request protocol to the instrument through the OBD diagnostic interface, the instrument comprises a data acquisition module, a protocol conversion module, a transmission module and a control module, the data acquisition module, the protocol conversion module and the transmission module are all electrically connected to a controller, the data acquisition module is used to obtain diagnostic response data from the electronic control unit after receiving a diagnostic request, the protocol conversion module is used to convert the acquired diagnostic response data into a return response data packet consistent with the diagnostic device request protocol, the control module is used to control the transmission module to transmit the return response data packet to the diagnostic device; the diagnostic device is also used to run a fault identification operation according to the return response data packet to generate a diagnostic operation result; The instrument further includes a fault identification module, the fault identification module is electrically connected to the control module, and the fault identification module is used to run a fault identification operation according to the acquired diagnostic response data and generate an instrument operation result; It also includes a wireless communication module, which is connected to the instrument through wireless communication with the mobile terminal to update the firmware or software of the instrument so that the instrument can be compatible with new standards and protocols; It also includes a user end, which is communicatively connected to the instrument and the diagnostic device. The instrument also includes a recording module. The user end is used to receive instrument operation results and diagnostic operation results, and generate user solutions. The fault identification module is also used to run the fault identification operation for a second time after the fault is solved, and generate a secondary instrument operation result. If the fault has been solved in the secondary instrument operation result, the recording module generates a fault log record.

4. The OBD diagnostic system based on instrumentation according to claim 3 is characterized in that: The diagnostic response data includes real-time fault data, historical fault data and fault freeze frame data.

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