SENT Sensor Interface Circuit Fault Diagnosis System, Method and Storage Medium

Abstract

The present invention relates to the technical field of automotive electronic fault diagnosis, and particularly relates to a fault diagnosis system, method and storage medium for a SENT sensor interface circuit. It includes an MCU, resistors R1 and R2, a capacitor and a pull-up resistor. One end of the pull-up resistor is connected to the power supply, and the other end is grounded through the capacitor. The SENT sensor signal input end of the system is connected to the ICU signal capture interface of the MCU through resistor R1, and the SENT sensor signal input end of the system is connected to the SENT signal input interface of the MCU through resistor R2. The MCU is used to perform edge counting and level status reading on the input signal of the ICU signal capture interface to achieve fault diagnosis of the SENT sensor interface circuit. By performing edge counting on the input signal through the ICU signal capture interface, fault diagnosis of the SENT sensor interface circuit can be achieved, avoiding the phenomenon of misdiagnosing normal signals as short-circuit to power supply or open-circuit faults caused by just continuously collecting when the SENT signal is at a high level within a filtering period.

Description

Technical Field

[0001] The present invention relates to the technical field of automotive electronic fault diagnosis, and particularly relates to a fault diagnosis system, method and storage medium for a SENT sensor interface circuit. Background Art

[0002] The SENT (Single Edge Nibble Transmission) protocol, namely the single-edge half-byte transmission protocol, is a new standard (SAE J2716) for automotive sensor and ECU communication introduced by the SAE Association. It is a digital signal transmission protocol for single-wire transmission, with higher transmission accuracy and speed. The SENT signal uses a 5V logic level and transmits data in frames. Each frame consists of pulses of different widths, i.e., half-bytes. The SENT frame is composed of a synchronization segment signal, a status segment signal, a fast channel segment signal, a CRC check segment signal, and an optional stop segment signal (refer to Figure 1 ). The SENT frame uses a tick as the minimum time unit. One tick is usually 3 μs, and the length range of a complete SENT frame is 154 - 270 ticks.

[0003] The diagnosis scope of faults in the SENT sensor interface circuit is that the sensor signal is short-circuited to ground, short-circuited to power supply, and open circuit. Currently, the SENT signal interface circuit solution usually uses an MCU with a SENT module, directly connecting the sensor SENT input signal to the MCU SENT signal input interface, and at the same time leading out the SENT signal to the DIO interface of the MCU to implement the circuit fault diagnosis function (refer to Figure 2 ). In software, the level status of the DIO diagnostic signal input interface is polled and read. When the sensor signal is normal, the DIO interface level is sometimes high and sometimes low; when the sensor signal is short-circuited to ground, the DIO interface level is constantly low; when the sensor signal is short-circuited to power supply or open circuit, the DIO interface level is constantly high.

[0004] In software processing, the fault state of the circuit is determined according to the status of the DIO level and through appropriate filtering. This method of judging faults only by collecting the SENT signal level through a single DIO interface has the disadvantages of the possibility of misdiagnosis and a long filtering time. For example, during a filtering period, it may happen that the SENT signal is continuously collected just when it is at a high level. At this time, although the signal is normal, an incorrect diagnosis result of short-circuited to power supply or open circuit will be given. Summary of the Invention

[0005] The object of the present invention is to aim at the defects of the prior art and provide a fault diagnosis system, method and storage medium for a SENT sensor interface circuit, which can avoid diagnosing a normal SENT signal as a short-circuited to power supply or open circuit fault signal.

[0006] The present invention provides a fault diagnosis system for a SENT sensor interface circuit, which includes an MCU, resistors R1, R2, a capacitor and a pull-up resistor. One end of the pull-up resistor is connected to a power supply, and the other end is grounded through the capacitor. The SENT sensor signal input terminal of the system is connected to the ICU signal capture interface of the MCU through resistor R1, and the SENT sensor signal input terminal of the system is connected to the SENT signal input interface of the MCU through resistor R2. The MCU is used for performing edge counting and level state reading on the input signal of the ICU signal capture interface to achieve fault diagnosis of the SENT sensor interface circuit.

[0007] Preferably, when the edge count value of the input signal of the ICU signal capture interface of the MCU is not 0 within a diagnostic time period, it is determined that there is no fault; when the edge count value of the MCU is 0 within a diagnostic time period, it is determined that there is a fault.

[0008] Preferably, when the MCU determines that there is a fault;

[0009] If the input signal received by the ICU signal capture interface is at a low level, it is determined that there is a short circuit to ground fault in the SENT sensor interface circuit;

[0010] If the input signal received by the ICU signal capture interface is at a high level, it is determined that there is a short circuit to the power supply or an open circuit fault in the SENT sensor interface circuit.

[0011] Preferably, it further includes resistors R3 to R5 and a triode. One ends of resistors R4 and R5 are both connected to the base of the triode. The other end of resistor R4 is connected to the diagnostic control output interface of the MCU. The other end of resistor R5 and the emitter of the triode are both grounded. One end of resistor R3 is connected to the collector of the triode, and the other end is connected between the pull-up resistor and resistor R1.

[0012] Preferably, the resistance value of the pull-up resistor is 4.7 KΩ.

[0013] Preferably, the MCU is further used for driving the triode to conduct and reading the level state of the input signal of the ICU signal capture interface after the triode conducts to distinguish between the short circuit to the power supply fault and the open circuit fault.

[0014] Preferably, when the level of the input signal of the ICU signal capture interface is at a high level after the triode conducts, it is determined that there is a short circuit to the power supply fault in the SENT sensor interface circuit;

[0015] When the level of the input signal of the ICU signal capture interface is at a low level after the triode conducts, it is determined that there is an open circuit fault in the SENT sensor interface circuit.

[0016] The present invention also provides a diagnostic method, including:

[0017] Reading the edge count value of the input signal of the ICU signal capture interface within a diagnostic time period. If the edge count value is not 0, it is determined that there is no fault; if the edge count value is 0, it is determined that there is a fault.

[0018] When it is determined that there is a fault, further obtaining the level state of the input signal of the ICU signal capture interface.

[0019] If the level state is low level, it is determined that there is a short - to - ground fault in the SENT sensor interface circuit.

[0020] If the level state is high level, it is determined that there is a short - to - power - supply or open - circuit fault in the SENT sensor interface circuit.

[0021] Preferably, when it is determined that there is a short - to - power - supply or open - circuit fault in the SENT sensor interface circuit, it further includes:

[0022] The MCU outputs a high - level driving signal to the triode through the diagnostic control output interface. After the triode conducts, the level state of the input signal of the ICU signal capture interface is read again.

[0023] If the level state is high level, it is determined that there is a short - to - power - supply fault in the SENT sensor interface circuit.

[0024] If the level state is low level, it is determined that there is an open - circuit fault in the SENT sensor interface circuit.

[0025] The present invention also provides a computer - readable storage medium, which stores a computer program. When the computer program is executed by a processor, the steps of the above - mentioned method are implemented.

[0026] The beneficial effects of the present invention are as follows:

[0027] 1. Utilize the ICU signal capture interface of the MCU, so that the SENT sensor signal of the system is also input to the ICU signal capture interface of the MCU. By performing edge counting on the input signal through the ICU signal capture interface, the fault diagnosis of the SENT sensor interface circuit can be realized. Among them, the edge count value of the normal signal is not 0, and when an electrical fault occurs in the SENT sensor, the edge count value must be 0, thereby distinguishing the normal signal from the fault signal and avoiding the phenomenon of misdiagnosing the normal signal as a short - to - power - supply or open - circuit fault caused by just continuously collecting when the SENT signal is at a high level within a filtering period.

[0028] 2. The ICU signal capture interface can also obtain the level status. After initially distinguishing normal signals and fault signals through edge counting, short - circuit - to - ground faults and short - circuit - to - power - supply or open - circuit faults can be further identified through the level status.

[0029] 3. A triode drive circuit is also set. The MCU turns on the triode and reads the level status of the input signal of the ICU signal capture interface after the triode is turned on, and can also distinguish short - circuit - to - power - supply faults and open - circuit faults. It solves the defect that in the existing technical solutions, due to the pull - up resistor in the sensor signal processing circuit, the manifestations of short - circuit - to - power - supply and open - circuit faults are the same and cannot be distinguished. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the composition of the SENT signal;

[0031] Figure 2 It is a schematic diagram of the system connection for diagnosing the existing SENT sensor signal processing circuit with a pull - up resistor;

[0032] Figure 3 It is a schematic diagram of the system connection of the present invention;

[0033] Figure 4 It is a schematic diagram of the diagnostic method flow of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] In order to make the technical problems, technical solutions and beneficial effects to be solved by this application clearer, the following further details this application in conjunction with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit this application.

[0035] In the following description, specific details such as specific system structures and technologies are presented for the purpose of illustration rather than limitation, so as to thoroughly understand the embodiments of this application. However, those skilled in the art should clearly understand that this application can also be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well - known systems, devices, circuits and methods are omitted to avoid unnecessary details from interfering with the description of this application.

[0036] It should be understood that when used in the specification of this application and the appended claims, the term "comprising" indicates the presence of the described features, wholes, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their combinations.

[0037] It should also be understood that the term "and / or" as used in the specification and appended claims of this application refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0038] As used in the specification and appended claims of this application, the term "if" may be construed, depending on the context, as "when", "once", "in response to determining", or "in response to detecting". Similarly, the phrases "if determined" or "if [the described condition or event] is detected" may be construed, depending on the context, to mean "once determined", "in response to determining", "once [the described condition or event] is detected", or "in response to detecting [the described condition or event]".

[0039] In addition, in the description of the specification and appended claims of this application, the terms "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be construed as indicating or implying relative importance.

[0040] Reference to "one embodiment" or "some embodiments" or the like described in the specification of this application means that a specific feature, structure, or characteristic described in connection with that embodiment is included in one or more embodiments of this application. Thus, statements such as "in one embodiment", "in some embodiments", "in other some embodiments", "in still other embodiments", etc. that appear in different places in this specification do not necessarily all refer to the same embodiment, but mean "one or more but not all embodiments", unless otherwise specifically emphasized in another way. The terms "comprising", "including", "having" and their variants all mean "including but not limited to", unless otherwise specifically emphasized in another way. "Plurality" means "two or more".

[0041] Embodiment 1

[0042] Figure 3 shows a schematic structural diagram of a SENT sensor interface circuit fault diagnosis system provided by a preferred embodiment ( Figure 3 shows a first embodiment) of this application. For the sake of convenience of description, only the parts related to this embodiment are shown and are described in detail as follows:

[0043] The present invention provides a fault diagnosis system for a SENT sensor interface circuit, which includes an MCU, resistors R1, R2, capacitors, and a pull-up resistor. One end of the pull-up resistor is connected to the power supply, and the other end is grounded through a capacitor. The SENT sensor signal input terminal of the system is connected to the ICU signal capture interface of the MCU through resistor R1, and the SENT sensor signal input terminal of the system is connected to the SENT signal input interface of the MCU through resistor R2. The MCU is used to perform edge counting and read the level state of the input signal at the ICU signal capture interface, so as to realize the fault diagnosis of the SENT sensor interface circuit.

[0044] In one embodiment, when the edge count value of the input signal at the ICU signal capture interface of the MCU is not 0 within a diagnostic time period, it is determined that there is no fault; when the edge count value of the MCU is 0 within a diagnostic time period, it is determined that there is a fault.

[0045] In one embodiment, when the MCU determines that there is a fault;

[0046] If the input signal received at the ICU signal capture interface is at a low level, it is determined that there is a short-to-ground fault in the SENT sensor interface circuit;

[0047] If the input signal received at the ICU signal capture interface is at a high level, it is determined that there is a short-to-power or open-circuit fault in the SENT sensor interface circuit.

[0048] By utilizing the ICU signal capture interface of the MCU, the SENT sensor signal of the system is also input to the ICU signal capture interface of the MCU. Edge counting is performed on the input signal through the ICU signal capture interface, and the fault diagnosis of the SENT sensor interface circuit can be realized. Among them, the edge count value of a normal signal is not 0, and when an electrical fault occurs in the SENT sensor, the edge count value must be 0, so that the normal signal and the fault signal can be distinguished, avoiding the phenomenon of misdiagnosing a normal signal as a short-to-power or open-circuit fault caused by just continuously collecting when the SENT signal is at a high level within a filtering period. The ICU signal capture interface can also obtain the level state. After initially distinguishing the normal signal and the fault signal through edge counting, the short-to-ground fault and the short-to-power or open-circuit fault can be further identified through the level state.

[0049] In one embodiment, it further includes resistors R3 to R5 and a triode. One ends of the resistors R4 and R5 are both connected to the base of the triode. The other end of the resistor R4 is connected to the diagnostic control output interface of the MCU. The other end of the resistor R5 and the emitter of the triode are both grounded. One end of the resistor R3 is connected to the collector of the triode, and the other end is connected between the pull-up resistor and the resistor R1.

[0050] In one embodiment, the resistance value of the pull-up resistor is 4.7 KΩ.

[0051] In one embodiment, the MCU is further configured to distinguish between a short-to-power supply fault and an open-circuit fault by driving the triode to conduct and reading the level state of the input signal at the ICU signal capture interface after the triode conducts.

[0052] In one embodiment, when the level of the input signal at the ICU signal capture interface is high after the triode conducts, it is determined that there is a short-to-power supply fault in the SENT sensor interface circuit;

[0053] When the level of the input signal at the ICU signal capture interface is low after the triode conducts, it is determined that there is an open-circuit fault in the SENT sensor interface circuit.

[0054] The MCU can also distinguish between a short-to-power supply fault and an open-circuit fault by driving the triode to conduct and reading the level state of the input signal at the ICU signal capture interface after the triode conducts. It solves the defect that in the prior art solutions, the short-to-power supply and open-circuit faults have the same manifestations and cannot be distinguished due to the pull-up resistor in the sensor signal processing circuit.

[0055] In summary, the system can diagnose and distinguish electrical faults in the SENT sensor interface circuit, including short-to-ground, short-to-power supply, and open-circuit faults. In the circuit design, the SENT sensor signal input is directly connected to the MCU SENT signal interface and also to the ICU input signal capture interface of the MCU. This interface can not only directly read the signal level state but also capture the edges of the signal and count the signal edges. When the sensor signal is normal, the edge count value is not 0 within a diagnostic time period. When the sensor has an electrical fault, the original signal at the ICU input signal interface is a constant high level or low level, and the edge count value is 0 within a diagnostic cycle. At this time, the level state of the signal is read again to determine whether there is a short-to-ground. If the level is low, it is diagnosed that a short-to-ground fault has occurred. If the level is high, it is diagnosed that a short-to-power supply or open-circuit fault has occurred.

[0056] In addition, the MCU diagnostic control output interface can be further used to distinguish between a short-to-power supply or open-circuit fault. First, the interface outputs a high level to drive the triode Q to conduct, and then the level state of the ICU input signal is read. If it is a high level, it is diagnosed as a short-to-power supply fault. If it is a low level, it is diagnosed as an open-circuit fault.

[0057] Embodiment 2

[0058] As Figure 4 shown, the present invention also provides a diagnostic method, including:

[0059] Read the edge count value of the input signal of the ICU signal capture interface within a diagnostic time period. If the edge count value is not 0, it is judged as no fault. If the edge count value is 0, it is judged that a fault exists;

[0060] When it is judged that a fault exists, further obtain the level state of the input signal of the ICU signal capture interface;

[0061] If the level state is low level, it is judged that there is a short - to - ground fault in the SENT sensor interface circuit;

[0062] If the level state is high level, it is judged that there is a short - to - power - supply or open - circuit fault in the SENT sensor interface circuit.

[0063] In one embodiment, when it is judged that there is a short - to - power - supply or open - circuit fault in the SENT sensor interface circuit, it further includes:

[0064] The MCU outputs a high - level drive signal to the triode through the diagnostic control output interface. After the triode conducts, read the level state of the input signal of the ICU signal capture interface again;

[0065] If the level state is high level, it is judged that there is a short - to - power - supply fault in the SENT sensor interface circuit;

[0066] If the level state is low level, it is judged that there is an open - circuit fault in the SENT sensor interface circuit.

[0067] Embodiment Three

[0068] This embodiment further elaborates on the diagnostic method of this system in combination with a specific hardware circuit design.

[0069] This system refers to Figure 3 for design. The MCU is equipped with a SENT module, a SENT signal input interface, and an ICU input signal capture interface. Among them, the SENT signal input interface is an interface of the SENT module. The SENT sensor signal is input to the MCU SENT signal interface and also connected to the ICU interface; the SENT signal has a pull - up resistor of 4.7KΩ; the diagnostic control output interface of the MCU is connected to the base of the triode Q. The resistance value of resistor R1 is 4.74.7KΩ, the resistance values of resistors R2 and R3 are 470Ω, and the resistance values of resistors R4 and R5 are 10KΩ.

[0070] The diagnostic method of this system is as follows:

[0071] a. The main function of the fault diagnosis module runs periodically (such as a 5 - ms period). First, read the edge count received by the ICU interface within one period. If the count value is not 0, it is judged as no fault, and the process ends;

[0072] b. If the edge count value is 0, it indicates a fault. Continue to read the ICU interface level status to determine the fault type. If the ICU level is low, it is determined as a short - to - ground fault, and the process ends.

[0073] c. If the ICU level is high, it indicates a short - to - power or open - circuit fault. Next, it is necessary to further distinguish between these two types of faults.

[0074] d. Control the diagnostic control output port to output a high level to drive the triode Q to conduct, and then read the ICU level status.

[0075] e. If the ICU level is low, it is diagnosed as an open - circuit fault, and the process ends.

[0076] f. If the ICU level is high, it is diagnosed as a short - to - power fault, and the process ends.

[0077] It should be understood that the specific order or hierarchy of steps in the disclosed process is an example of an exemplary method. Based on design preferences, it should be understood that the specific order or hierarchy of steps in the process can be rearranged without departing from the scope of the present disclosure. The appended method claims present the elements of the various steps in an exemplary order and are not intended to be limited to the specific order or hierarchy described.

[0078] In the above - mentioned detailed description, various features are combined in a single embodiment to simplify the present disclosure. This disclosure method should not be construed as reflecting the intention that the embodiments of the claimed subject matter require more features than those clearly stated in each claim. On the contrary, as reflected in the appended claims, the present invention is in a state with fewer features than all the features of the disclosed single embodiment. Therefore, the appended claims are hereby clearly incorporated into the detailed description, where each claim stands alone as a separate preferred embodiment of the present invention.

[0079] In order for any person skilled in the art to implement or use the present invention, the above - disclosed embodiments have been described. For those skilled in the art, various modification methods of these embodiments are obvious, and the general principles defined herein can also be applied to other embodiments without departing from the spirit and scope of the present disclosure. Therefore, the present disclosure is not limited to the embodiments given herein, but is consistent with the broadest scope of the principles and novel features disclosed in this application.

[0080] The foregoing description includes examples of one or more embodiments. Of course, it is not possible to describe all possible combinations of components or methods for the purpose of describing the above embodiments, but those of ordinary skill in the art should recognize that the various embodiments can be further combined and arranged. Therefore, the embodiments described herein are intended to cover all such changes, modifications, and variations that fall within the scope of the appended claims. In addition, with respect to the term "comprising" used in the specification or claims, this term is inclusive in a manner similar to the term "including", as is explained when "including" is used as a transitional word in a claim. In addition, any use of the term "or" in the specification or claims is intended to mean "non-exclusive or".

[0081] Those skilled in the art can also understand that the various illustrative logical blocks, units, and steps listed in the embodiments of the present invention can be implemented by electronic hardware, computer software, or a combination of both. To clearly show the interchangeability of hardware and software, the above various illustrative components, units, and steps have been generally described in terms of their functions. Whether such functions are implemented by hardware or software depends on the specific application and the design requirements of the entire system. Those skilled in the art can use various methods to implement the described functions for each specific application, but such implementation should not be construed as exceeding the scope of protection of the embodiments of the present invention.

[0082] The various illustrative logical blocks or units described in the embodiments of the present invention can be implemented or operated to perform the described functions by a general-purpose processor, a digital signal processor, an application specific integrated circuit (ASIC), a field programmable gate array or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination of the above designs. The general-purpose processor can be a microprocessor, and optionally, the general-purpose processor can also be any conventional processor, controller, microcontroller, or state machine. The processor can also be implemented by a combination of computing devices, such as a digital signal processor and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a digital signal processor core, or any other similar configuration.

[0083] In the embodiments of the present invention, the steps of the methods or algorithms described may be directly implemented in hardware, software modules executed by a processor, or a combination of both. The software modules may be stored in a RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium in the art. Exemplarily, the storage medium may be connected to the processor so that the processor can read information from the storage medium and write information to the storage medium. Optionally, the storage medium may also be integrated into the processor. The processor and the storage medium may be provided in an ASIC, and the ASIC may be provided in a user terminal. Optionally, the processor and the storage medium may also be provided in different components of the user terminal.

[0084] In one or more exemplary designs, the above-described functions of the embodiments of the present invention may be implemented in hardware, software, firmware, or any combination of the three. If implemented in software, these functions may be stored on a computer-readable medium or transmitted on a computer-readable medium in the form of one or more instructions or codes. The computer-readable medium includes a computer storage medium and a communication medium that facilitates the transfer of a computer program from one place to another. The storage medium may be any available medium accessible by a general or special computer. For example, such a computer-readable medium may include, but is not limited to, RAM, ROM, EEPROM, CD-ROM, or other optical disk storage, magnetic disk storage, or other magnetic storage devices, or any other medium that can be used to carry or store program code in the form of instructions or data structures and other forms readable by a general or special computer, or a general or special processor. In addition, any connection may be appropriately defined as a computer-readable medium. For example, if software is transmitted from a website, server, or other remote resource via a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless means such as infrared, wireless, and microwave, it is also included in the defined computer-readable medium. The disks and discs mentioned herein include compact disks, laser disks, optical discs, DVDs, floppy disks, and Blu-ray discs. Disks usually reproduce data magnetically, while discs usually reproduce data optically by laser. The above combinations may also be included in the computer-readable medium.

[0085] The above-described embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit them. Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements for some of the technical features. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A fault diagnosis system for a SENT sensor interface circuit, characterized in that: It includes an MCU, resistors R1, R2, a capacitor, and a pull-up resistor. One end of the pull-up resistor is connected to the power supply, and the other end is grounded through the capacitor. The SENT sensor signal input terminal of the system is connected to the ICU signal capture interface of the MCU through resistor R1, and the SENT sensor signal input terminal of the system is connected to the SENT signal input interface of the MCU through resistor R2. The MCU is used to perform edge counting and level status reading on the input signal of the ICU signal capture interface to achieve fault diagnosis of the SENT sensor interface circuit; When the edge count value of the input signal at the ICU signal capture interface of the MCU is not 0 within a diagnostic time period, it is judged as no fault; when the edge count value of the MCU is 0 within a diagnostic time period, it is judged as a fault; When the MCU judges that there is a fault; If the input signal received at the ICU signal capture interface is low level, it is judged that there is a short-to-ground fault in the SENT sensor interface circuit; If the input signal received at the ICU signal capture interface is high level, it is judged that there is a short-to-power or open-circuit fault in the SENT sensor interface circuit; It also includes resistors R3 to R5 and a triode. One ends of resistors R4 and R5 are both connected to the base of the triode. The other end of resistor R4 is connected to the diagnostic control output interface of the MCU. The other end of resistor R5 and the emitter of the triode are both grounded. One end of resistor R3 is connected to the collector of the triode, and the other end is connected between the pull-up resistor and resistor R1; The MCU is also used to drive the triode to conduct and read the level status of the input signal at the ICU signal capture interface after the triode conducts to distinguish between short-to-power and open-circuit faults.

2. The SENT sensor interface circuit fault diagnosis system according to claim 1, wherein: The resistance value of the pull-up resistor is 4.7 KΩ.

3. The SENT sensor interface circuit fault diagnosis system according to claim 1, characterized in that: When the level of the input signal at the ICU signal capture interface is high level after the triode conducts, it is judged that there is a short-to-power fault in the SENT sensor interface circuit; When the level of the input signal at the ICU signal capture interface is low level after the triode conducts, it is judged that there is an open-circuit fault in the SENT sensor interface circuit.

4. A diagnostic method for the system according to any one of claims 1 to 3, characterized in that: Read the edge count value of the input signal at the ICU signal capture interface within a diagnostic time period. When the edge count value is not 0, it is judged as no fault. When the edge count value is 0, it is judged as a fault; When it is judged that there is a fault, further obtain the level status of the input signal at the ICU signal capture interface; If the level status is low level, it is judged that there is a short-to-ground fault in the SENT sensor interface circuit; If the level status is high level, it is judged that there is a short-to-power or open-circuit fault in the SENT sensor interface circuit.

5. The diagnostic method according to claim 4, wherein When it is judged that there is a short-to-power or open-circuit fault in the SENT sensor interface circuit, it further includes: The MCU outputs a high-level drive signal to the triode through the diagnostic control output interface. After the triode conducts, read the level status of the input signal at the ICU signal capture interface again; If the level state is a high level, it is determined that there is a short - circuit - to - power supply fault in the SENT sensor interface circuit; If the level state is a low level, it is determined that there is an open - circuit fault in the SENT sensor interface circuit.

6. A computer-readable storage medium storing a computer program, characterized in that: When the computer program is executed by a processor, it implements the steps of the method according to claim 4 or 5.

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