A process-oriented pre-diagnosis method for vehicle lamps

Abstract

The application discloses a process-oriented car lamp pre-diagnosis method, comprising the following steps: S1, calibrating the sampling period standard value of the chip of a sampling car lamp; S2, sampling the chip of a non-faulty car lamp to obtain car lamp operation data, and after sampling the car lamp operation data of n automobile ignition periods, entering S3; S3, obtaining the change trend of the car lamp operation data of the non-faulty car lamp according to the car lamp operation data of the n automobile ignition periods; S4, detecting whether the chip of the car lamp generates a level fault signal in the use process of the car lamp, if yes, entering S5, if not, monitoring and sampling the data of the chip; S5, sampling the data of the chip and judging whether the change trend of the data is consistent with the change trend of the car lamp operation data of the non-faulty car lamp, if yes, judging whether the car lamp fault alarm is a false alarm, if not, entering the step of issuing a car lamp fault alarm. The application makes a fault trend judgment on a single level fault feedback car lamp switching power supply, and the effect that whether the car lamp is faulty can be predicted in advance is achieved.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of vehicle lamp pre-diagnosis methods, and particularly relates to a process-oriented vehicle lamp pre-diagnosis method. BACKGROUND

[0002] When the switching power supply of the existing vehicle lamp fails, the fault feedback loop for the switching power supply chip thereof can only feed back a single level fault signal, so it can only produce a fault or no fault state feedback, resulting in a single feedback signal, and the fault detection scheme is in a real-time monitoring mode, so it cannot monitor and predict the failure trend of the switching power supply of the vehicle lamp in the entire life cycle. At the same time, due to the single structure of the feedback loop, it is easy to cause misjudgment due to signal interference and logic errors. SUMMARY

[0003] The purpose of the application is to provide a process-oriented vehicle lamp pre-diagnosis method to make a failure trend judgment for a single level fault feedback vehicle lamp switching power supply, so as to predict whether the vehicle lamp fails in advance and ensure stable operation of the switching power supply system.

[0004] To achieve the above-mentioned purpose of the application, the technical scheme adopted by the application is as follows:

[0005] A process-oriented vehicle lamp pre-diagnosis method, comprising the following steps:

[0006] Step S1. Calibrating the sampling cycle standard value of the switching power supply chip of the sampled vehicle lamp;

[0007] Step S2. Sampling the switching power supply chip of the non-fault vehicle lamp to obtain vehicle lamp operation data, and after sampling the vehicle lamp operation data of n automobile ignition cycles, entering step S3;

[0008] Step S3. Obtaining the change trend of the vehicle lamp operation data of the non-fault vehicle lamp according to the sampled vehicle lamp operation data of n automobile ignition cycles;

[0009] Step S4. During the use of the vehicle lamp, detecting whether the switching power supply chip of the vehicle lamp produces a level fault signal, if yes, entering step S5; if no, monitoring and sampling the data of the chip, and when the change trend of the data of the chip does not conform to the change trend of the vehicle lamp operation data of the non-fault vehicle lamp, entering step S6.1;

[0010] Step S5. Sampling the data of the chip and judging whether the change trend thereof conforms to the change trend of the vehicle lamp operation data of the non-fault vehicle lamp, if yes, entering step S6.2; if no, entering step S6.3;

[0011] Step S6.1. Issuing a vehicle lamp maintenance alarm and entering step S6.4;

[0012] Step S6.2. Determine whether the duration of the level fault signal generated by the switching power supply chip of the vehicle lamp is greater than the sampling period standard value, if yes, go to step S6.3; if no, issue a false alarm information of vehicle lamp fault, and go to step S6.4.

[0013] Step S6.3. Issue a vehicle lamp fault alarm, and go to step S6.4.

[0014] Step S6.4. End the flow.

[0015] The process-oriented vehicle lamp pre-diagnosis method of the present application first calculates the change trend of the vehicle lamp operation data of the non-fault vehicle lamp as a historical record, then compares the data of the switching power supply chip sampled during the use of the vehicle lamp with the historical record, and further determines whether the vehicle lamp has a fault.

[0016] Preferably, the vehicle lamp pre-diagnosis method further comprises a signal sampling and detection circuit applied to the switching power supply chip of the vehicle lamp; the signal sampling and detection circuit comprises a controller and a detection loop; the controller communicates with the switching power supply chip; and the output end of the detection loop is connected with the controller.

[0017] Preferably, the signal sampling and detection circuit further comprises a power supply device and an input signal; the power supply device supplies power to the switching power supply chip; and the input signal is connected with the input end of the detection loop.

[0018] Preferably, the switching power supply chip comprises a FAULT pin; and the switching power supply chip sends a level fault signal to the controller through the FAULT pin.

[0019] Preferably, the step S1 comprises: setting the sampling period standard value of the switching power supply chip as t typ , setting the voltage typical value as U typ , setting the current typical value as I typ , setting the temperature typical value as T typ , setting the boundary value of the voltage change trend as |K U , setting the boundary value of the voltage difference change trend as |K ΔU , setting the boundary value of the current change trend as |K I , setting the boundary value of the current difference change trend as |K ΔI , setting the boundary value of the temperature change trend as |K T , and setting the boundary value of the temperature difference change trend as |K ΔT .

[0020] Preferably, the step S2 comprises: sampling the voltage, current and temperature of the switching power supply chip of the non-fault vehicle lamp for n times of automobile ignition period, and calculating the average value of the voltage sampled for 1 to n-1 times and the average value of the current the average value of the temperature and the average value of the difference of the voltage is calculated the average value of the difference of the current the average value of the difference of the temperature wherein the calculation formula of the average value of the voltage is as follows:

[0021] wherein n≥2;

[0022] or wherein n=1.

[0023] Preferably, the step S3 comprises: when the sampled voltage of the switching power supply chip is U n , the current is I n , and the temperature is T n , the change trend K Un of the voltage, the change trend K ΔUn of the difference of the voltage, the change trend K In of the current, the change trend K ΔIn of the difference of the current, the change trend K Tn of the temperature, and the change trend K ΔTn of the difference of the temperature are calculated, and the hyperparameters λ and β are set, wherein the calculation formula of the change trend K Un of the voltage and the change trend K ΔUn of the difference of the voltage is as follows:

[0024] wherein n≥1;

[0025] wherein n≥2.

[0026] Preferably, the step S4 comprises:

[0027] Step S4.1. If it is detected that the switching power supply chip of the vehicle lamp does not generate the level fault signal, the voltage, the current, and the temperature of the switching power supply chip are sampled, and the corresponding voltage change trend K1, the voltage difference change trend K2, the current change trend K3, the current difference change trend K4, the temperature change trend K5, and the temperature difference change trend K6 are calculated.

[0028] Step S4.2. It is determined whether K1≥|KU| and K2≥|KΔU|, if yes, it is determined that the vehicle lamp does not have a fault and enters step S6.4, if not, it enters step S4.3.

[0029] Step S4.3. It is determined whether K3≥|KI| and K4≥|KΔI|, if yes, it is determined that the vehicle lamp does not have a fault and enters step S6.4, if not, it enters step S4.4.

[0030] Step S4.4. Determine whether K5≥|KT| and K6≥|KΔT|, if yes, determine that the car light is not malfunctioning and enter step S6.4, if no, determine that the car light is malfunctioning and enter step S6.1.

[0031] Preferably, the step S5 comprises:

[0032] Step S5.1. Sample the voltage, current, temperature of the switching power supply chip and calculate the corresponding voltage variation trend K7, voltage difference variation trend K8, current variation trend K9, current difference variation trend K10, temperature variation trend K11, and temperature difference variation trend K12. 10 11 12 ;

[0033] Step S5.2. Determine whether K7≥|KU| and K8≥|KΔU|, if yes, enter step S6.3, if no, enter step S5.3;

[0034] Step S5.3. Determine whether K9≥|KI| and K10≥|KΔI|, if yes, enter step S6.3, if no, enter step S5.4;

[0035] Step S5.4. Determine whether K11≥|KT| and K12≥|KΔT|, if yes, enter step S6.3, if no, enter step S6.2.

[0036] Preferably, the step S5.2 further comprises: when it is determined that K7≥|K U | and K8≥|K ΔU |, the sampling point and sampling period of the switching power supply chip can be adjusted and return to step S5.1.

[0037] Beneficial effects:

[0038] The process-oriented car light pre-diagnosis method of the present application first calculates the variation trend of the car light running data of the non-malfunctioning car light as a historical record, then compares the data of the switching power supply chip sampled in the use process of the car light with the historical record, and further determines whether the car light is malfunctioning. BRIEF DESCRIPTION OF DRAWINGS

[0039] Fig. 1 Fig. 1 shows a flow chart of a process-oriented car light pre-diagnosis method of an embodiment;

[0040] Fig. 2 Fig. 2 shows a schematic diagram of a signal sampling and detection circuit of an embodiment;

[0041] Fig. 3 Fig. 3 shows a first timing diagram of a process-oriented car light pre-diagnosis method of an embodiment; ​​

[0042] Fig. 4 The diagram shown is a second timing diagram of a process-oriented vehicle headlight pre-diagnosis method according to an embodiment.

[0043] Figure Labels

[0044] 101. Power supply device; 102. Input signal; 200. Switching power supply chip; 201. FAULT pin; 300. Controller; 400. Detection circuit. Detailed Implementation

[0045] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings and other implementation methods can be obtained based on these drawings without any creative effort.

[0046] The technical solution of the present invention will be described in detail below with specific embodiments.

[0047] Example

[0048] like Figs. 1-4 As shown, this embodiment of a process-oriented vehicle headlight pre-diagnosis method includes the following steps:

[0049] Step S1. Calibrate the standard value of the sampling period of the switching power supply chip of the sampling vehicle light;

[0050] Step S2. Sample the switching power supply chip of the non-faulty headlights to obtain headlight operation data. Continue sampling headlight operation data for n car ignition cycles until step S3 is reached.

[0051] Step S3. Based on the sampled headlight operation data of n vehicle ignition cycles, obtain the changing trend of headlight operation data of non-faulty headlights;

[0052] Step S4. During the use of the vehicle lights, check whether the switching power supply chip of the vehicle lights generates a level fault signal. If yes, proceed to step S5; if no, monitor and sample the data of the chip. When the monitored data change trend of the chip does not match the change trend of the vehicle light operation data of the non-faulty vehicle lights, proceed to step S6.1.

[0053] Step S5. Sample the chip data and determine whether its trend of change matches the trend of the operating data of the non-faulty headlights. If yes, proceed to step S6.2; otherwise, proceed to step S6.3.

[0054] Step S6.1. Issue a headlight maintenance alarm and proceed to step S6.4;

[0055] Step S6.2. Determine whether the duration of the level fault signal generated by the switching power supply chip of the headlight is greater than the standard value of the sampling period. If yes, proceed to step S6.3; if no, issue a false alarm message for headlight fault and proceed to step S6.4.

[0056] Step S6.3. Issue a headlight malfunction alarm and proceed to step S6.4.

[0057] Step S6.4. Process ends.

[0058] Preferably, the vehicle headlight pre-diagnosis method further includes a signal sampling and detection circuit for the switching power supply chip 200 applied to the vehicle headlight; the signal sampling and detection circuit includes a controller 300 and a detection circuit 400; the controller 300 communicates with the switching power supply chip 200; the output terminal of the detection circuit 400 is connected to the controller 300.

[0059] Preferably, the signal sampling and detection circuit further includes a power supply device 101 and an input signal 102; the power supply device 101 supplies power to the switching power supply chip 200; the input signal 102 is connected to the input terminal of the detection circuit 400.

[0060] Preferably, the switching power supply chip 200 includes a FAULT pin 201; the switching power supply chip 200 sends a level fault signal to the controller 300 through the FAULT pin 201.

[0061] Preferably, step S1 includes: calibrating the typical value of the sampling period of the switching power supply chip 200 as t. typ The typical voltage value is U typ The typical current value is I typ Typical temperature value is T typ Boundary value of voltage change trend |K U | Boundary value of voltage difference variation trend |K ΔU | Boundary value of current variation trend |K I | Boundary value of the current difference variation trend | K ΔI | Boundary value of temperature change trend | K T | Boundary value of temperature difference variation trend | K ΔT |

[0062] Preferably, step S2 includes: sampling the voltage, current, and temperature of the switching power supply chip 200 of the non-faulty vehicle lights during n vehicle ignition cycles, and calculating the average value of the voltage sampled from 1 to n-1 times. Average current average temperature And calculate the average value of the voltage difference. Average difference of current Average temperature difference The formula for calculating the average voltage is as follows:

[0063] Where n≥2;

[0064] or Where n = 1.

[0065] Preferably, step S3 includes: when the sampled voltage of the switching power supply chip 200 is U n The current is I n Temperature T n When calculating the voltage change trend K Un The trend of voltage difference K ΔUn The trend of current change K In The trend of change in current difference K ΔIn Temperature variation trend K Tn The trend of temperature difference K ΔTn Set hyperparameters λ and β, where the voltage variation trend K is calculated. Un and the trend of voltage difference K ΔUn The calculation formula is as follows:

[0066] Where n≥1;

[0067] Where n≥2.

[0068] Similarly, by replacing U with I in the above formula, the corresponding trend of current change and the trend of current difference change can be calculated; by replacing U with T in the above formula, the corresponding trend of temperature change and the trend of temperature difference change can be calculated.

[0069] Preferably, step S4 includes:

[0070] Step S4.1. If the switching power supply chip 200 of the vehicle headlight is found not to generate a level fault signal, the voltage, current and temperature of the switching power supply chip 200 are sampled and the corresponding voltage change trend K1, voltage difference change trend K2, current change trend K3, current difference change trend K4, temperature change trend K5 and temperature difference change trend K6 are calculated.

[0071] Step S4.2. Determine whether K1≥|KU| and K2≥|KΔU|. If yes, determine that the headlights are not faulty and proceed to step S6.4. If no, proceed to step S4.3.

[0072] Step S4.3. Determine whether K3≥|KI| and K4≥|KΔI|. If yes, determine that the headlights are not faulty and proceed to step S6.4. If no, proceed to step S4.4.

[0073] Step S4.4. Determine whether K5≥|KT| and K6≥|KΔT|. If yes, determine that the headlights are not faulty and proceed to step S6.4. If no, determine that the headlights are faulty and proceed to step S6.1.

[0074] Preferably, step S5 includes:

[0075] Step S5.1. Sample the voltage, current, and temperature of the switching power supply chip 200 and calculate the corresponding voltage change trend K7, voltage difference change trend K8, current change trend K9, and current difference change trend K1. 10 Temperature change trend K 11 Trend of temperature difference K 12 ;

[0076] Step S5.2. Determine whether K7≥|KU| and K8≥|KΔU|. If yes, proceed to step S6.3; otherwise, proceed to step S5.3.

[0077] Step S5.3. Determine whether K9≥|KI| and K10≥|KΔI|. If yes, proceed to step S6.3; otherwise, proceed to step S5.4.

[0078] Step S5.4. Determine whether K11≥|KT| and K12≥|KΔT|. If yes, proceed to step S6.3; otherwise, proceed to step S6.2.

[0079] Preferably, step S5.2 further includes: when it is determined that K7≥|K U |and K8≥|K ΔU If necessary, the sampling points and sampling period of the switching power supply chip 200 can be adjusted and the process can return to step S5.1.

[0080] Furthermore, if at least one of the judgment results in step S5.2 is "yes", then it is necessary to resample and judge again. If at least one of the judgment results is still "yes", it means that the headlight has indeed malfunctioned and a fault feedback message should be issued. Otherwise, the sampling algorithm of the switching power supply chip 200 should be adjusted (sampling points doubled, sampling period doubled).

[0081] Furthermore, if the fault is still detected after adjusting the sampling algorithm (doubling the sampling points and doubling the sampling period), it means that the fault has always existed, that is, the switching power supply chip 200 has indeed failed. Otherwise, it means that the switching power supply chip 200 may be affected by interference or logic errors, resulting in a false alarm, and the fault alert will be canceled.

[0082] Furthermore, in step S6.2, if the duration of the level fault signal generated by the switching power supply chip of the headlight is less than the set time threshold, the headlight fault is determined to be a false alarm.

[0083] Specifically, in the signal sampling and detection circuit of this embodiment, the controller 300 acquires the level signal of the FAULT pin 201 of the switching power supply chip 200. When the FAULT pin is not equal to 1, the switching power supply chip 200 does not generate a level fault signal, and when the FAULT pin is equal to 1, the switching power supply chip 200 generates a level fault signal.

[0084] Specifically, in the signal sampling and detection circuit of this embodiment, the controller 300 sends an EN enable signal to control the switching power supply chip 200 to work, and detects the input signal 102 through the detection circuit 400 to control whether to output the LED lights of the vehicle lights (all LED lights of the vehicle lights are connected to the switching power supply chip 200), and samples and calculates the input and output voltage, current and temperature values ​​of the switching power supply chip 200. At the same time, it detects whether the switching power supply chip 200 is working properly by checking the status reminder FAULT pin 201.

[0085] Specifically, in this embodiment, the power supply device 101 is a battery; the voltage difference in this embodiment refers to the difference between the input voltage and the output voltage of the switching power supply chip 200; the current difference in this embodiment refers to the difference between the input current and the output current of the switching power supply chip 200; and the temperature difference in this embodiment refers to the difference between the internal temperature and the external temperature of the switching power supply chip 200.

[0086] Specifically, in this embodiment, a process-oriented vehicle headlight pre-diagnosis method uses the vehicle headlight operation data of non-faulty headlights as historical data. At the same time, it also saves the data of the voltage, current, and temperature change trends of the switching power supply chip 200 when they are normal and the data when the fault is determined to be a false alarm, in order to compensate for the historical data.

[0087] Specifically, the process-oriented vehicle headlight pre-diagnosis method of this embodiment can judge the fault trend of the chip by sampling the voltage, current and temperature of the switching power supply chip 200 and comparing it with historical data, so as to predict the chip failure in advance or reduce misjudgment.

[0088] Specifically, this embodiment of a process-oriented vehicle headlight pre-diagnosis method samples voltage and current parameters, monitors temperature changes, and adjusts the sampling period when the switching power supply is started. It continuously records and adjusts relevant parameters during the operation of the headlight to predict the trend of fault occurrence and reduce the probability of fault misjudgment.

[0089] Specifically, the process-oriented vehicle headlight pre-diagnosis method of this embodiment performs a successive comparison of the input and output states of the switching power supply chip 200 and its internal states (temperature, voltage characteristics) with historical records each time the headlight is started. This updates the quality judgment parameters of the switching power supply chip 200 in real time, and makes a fault trend judgment for the headlight switching power supply with single-level fault feedback (error state output reminder FAULT signal). This achieves the effect of predicting failure in advance or reducing the probability of false alarms, and ensures the stable operation of the switching power supply system.

[0090] This invention is applicable to headlights, taillights, and switching power supply solutions or other linear constant current solutions with a single feedback level signal.

[0091] The switching power supply chip 200 product involving a single feedback level signal, software strategies that calculate numerical trends using parameters such as voltage, current, and temperature, or compare them with historical values, or algorithms similar to pre-diagnostic strategies, should all be within the scope of protection of this invention.

[0092] The embodiments of the process-oriented vehicle headlight pre-diagnosis method provided by the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention, and the descriptions of the embodiments above are only for the purpose of helping to understand the core ideas of the present invention. It should be noted that those skilled in the art can make several improvements and modifications to the present invention without departing from the principles of the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A process-oriented method for pre-diagnostic analysis of vehicle lights, characterized in that, Includes the following steps: Step S1. Calibrate the standard value of the sampling period of the switching power supply chip of the sampling vehicle light; Step S2. Sample the switching power supply chip of the non-faulty headlights to obtain headlight operation data. Continue sampling headlight operation data for n car ignition cycles until step S3 is reached. Step S3. Based on the sampled headlight operation data of n vehicle ignition cycles, obtain the changing trend of headlight operation data of non-faulty headlights; Step S4. During the use of the vehicle lights, check whether the switching power supply chip of the vehicle lights generates a level fault signal. If so, proceed to step S5. If not, monitor and sample the chip's data. When the monitored chip's data change trend does not match the change trend of the vehicle light operation data of the non-faulty vehicle light, proceed to step S6.

1. Step S5. Sample the chip data and determine whether its trend of change matches the trend of the operating data of the non-faulty headlights. If yes, proceed to step S6.2; otherwise, proceed to step S6.

3. Step S6.

1. Issue a headlight maintenance alarm and proceed to step S6.4; Step S6.

2. Determine whether the duration of the level fault signal generated by the switching power supply chip of the headlight is greater than the standard value of the sampling period. If yes, proceed to step S6.3; if no, issue a false alarm message for headlight fault and proceed to step S6.

4. Step S6.

3. Issue a headlight malfunction alarm and proceed to step S6.4; Step S6.

4. Process ends; Step S1 includes: calibrating the standard value of the sampling period of the switching power supply chip (200) to t. typ The typical voltage value is U typ The typical current value is I typ Typical temperature value is T typ Boundary value of voltage change trend |K U | Boundary value of voltage difference variation trend |K ΔU | Boundary value of current variation trend |K I | Boundary value of the current difference variation trend | K ΔI | Boundary value of temperature change trend | K T | Boundary value of temperature difference variation trend | K ΔT |; Step S4 includes: Step S4.

1. If the switching power supply chip (200) of the vehicle headlight is not detected to generate a level fault signal, the voltage, current and temperature of the switching power supply chip (200) are sampled and the corresponding voltage change trend K1, voltage difference change trend K2, current change trend K3, current difference change trend K4, temperature change trend K5 and temperature difference change trend K6 are calculated. Step S4.

2. Determine whether K1≥|K U |and K2≥|K ΔU If yes, then determine that the headlights are not malfunctioning and proceed to step S6.4; otherwise, proceed to step S4.

3. Step S4.

3. Determine if K3 ≥ |K I |and K4≥|K ΔI If yes, then determine that the headlights are not malfunctioning and proceed to step S6.4; otherwise, proceed to step S4.

4. Step S4.

4. Determine if K5 ≥ |K T |and K6≥|K ΔT If yes, then the headlights are determined not to be faulty and proceed to step S6.4; otherwise, the headlights are determined to be faulty and proceed to step S6.

1.

2. The process-oriented vehicle headlight pre-diagnosis method according to claim 1, characterized in that, The vehicle headlight pre-diagnosis method further includes a signal sampling and detection circuit for a switching power supply chip (200) applied to the vehicle headlight; the signal sampling and detection circuit includes a controller (300) and a detection circuit (400); the controller (300) communicates with the switching power supply chip (200); the output terminal of the detection circuit (400) is connected to the controller (300).

3. The process-oriented vehicle headlight pre-diagnosis method according to claim 2, characterized in that, The signal sampling and detection circuit also includes a power supply device (101) and an input signal (102); the power supply device (101) supplies power to the switching power supply chip (200); the input signal (102) is connected to the input terminal of the detection circuit (400).

4. The process-oriented vehicle headlight pre-diagnosis method according to claim 2, characterized in that, The switching power supply chip (200) includes a FAULT pin (201); the switching power supply chip (200) sends a level fault signal to the controller (300) through the FAULT pin (201).

5. The process-oriented vehicle headlight pre-diagnosis method according to claim 1, characterized in that, Step S2 includes: sampling the voltage, current, and temperature of the switching power supply chip (200) of the non-faulty headlights during n vehicle ignition cycles, and calculating the average voltage of the samples from 1 to n-1. Average current average temperature And calculate the average voltage difference. Average difference of current Average temperature difference The formula for calculating the average voltage is as follows: Where n≥2; or Where n = 1.

6. The process-oriented vehicle headlight pre-diagnosis method according to claim 5, characterized in that, Step S3 includes: when the voltage of the sampled switching power supply chip (200) is U n The current is I n Temperature T n When calculating the voltage change trend K Un The trend of voltage difference K ΔUn The trend of current change K In The trend of change in current difference K ΔIn Temperature variation trend K Tn The trend of temperature difference K ΔTn Set hyperparameters λ and β, where the voltage variation trend K is calculated. Un and the trend of voltage difference K ΔUn The calculation formula is as follows: Where n≥1; Where n≥2.

7. The process-oriented vehicle headlight pre-diagnosis method according to claim 1, characterized in that, Step S5 includes: Step S5.

1. Sample the voltage, current, and temperature of the switching power supply chip (200) and calculate the corresponding voltage change trend K7, voltage difference change trend K8, current change trend K9, and current difference change trend K1. 10 Temperature change trend K 11 Trend of temperature difference K 12 ; Step S5.

2. Determine whether K7 ≥ |K U |and K8≥|K ΔU If yes, proceed to step S6.3; otherwise, proceed to step S5.

3. Step S5.

3. Determine if K9 ≥ |K I |and K 10 ≥|K ΔI If yes, proceed to step S6.3; otherwise, proceed to step S5.

4. Step S5.

4. Determine if K 11 ≥|K T |and K 12 ≥|K ΔT If yes, proceed to step S6.3; otherwise, proceed to step S6.

2.

8. The process-oriented vehicle headlight pre-diagnosis method according to claim 7, characterized in that, Step S5.2 further includes: when it is determined that K7≥|K U |and K8≥|K ΔU When the sampling point and sampling period of the switching power supply chip (200) are adjusted, the process returns to step S5.1.

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