Process-oriented vehicle lamp pre-diagnosis method

Abstract

The invention discloses a process-oriented vehicle lamp pre-diagnosis method. The process-oriented vehicle lamp pre-diagnosis method comprises the following steps: S1, calibrating a sampling period standard value of a chip of a sampling vehicle lamp; s2, sampling a chip of a non-fault automobile lamp to obtain automobile lamp operation data, and entering S3 until the automobile lamp operation data of n automobile ignition cycles are sampled; s3, according to the sampled automobile lamp operation data of the n automobile ignition periods, the change trend of the automobile lamp operation data of the automobile lamp without faults is obtained; s4, in the use process of the vehicle lamp, detecting whether a chip of the vehicle lamp generates a level fault signal or not, if so, entering S5, and if not, entering S5; if not, monitoring and sampling data of the chip; s5, sampling the data of the chip and judging whether the change trend of the data accords with the change trend of the vehicle lamp operation data of the vehicle lamp without the fault, and if so, judging whether the vehicle lamp fault alarm is a false alarm; if not, an automobile lamp fault alarm is sent out. Fault trend judgment is made for the vehicle lamp switching power supply with single level fault feedback, and the effect of predicting whether the vehicle lamp breaks down or not in advance is achieved.

Description

Technical Field

[0001] The invention belongs to the field of vehicle light pre-diagnosis methods, and in particular relates to a process-oriented vehicle light pre-diagnosis method. Background Art

[0002] When the switch power supply of the existing headlight fails, the fault feedback loop used for the switch power supply chip can only feedback a level fault signal, so it can only generate fault or no fault status feedback, resulting in a single feedback signal. In addition, this fault detection scheme adopts a real-time monitoring method, which makes it impossible to monitor and predict the fault trend of the switch power supply of the headlight throughout its life cycle. At the same time, due to the single feedback loop structure, it is easy to be misjudged by signal interference and logical errors. Summary of the invention

[0003] The purpose of the present invention is to provide a process-oriented vehicle lamp pre-diagnosis method, which makes a fault trend judgment for a vehicle lamp switch power supply with single-level fault feedback, so as to achieve the effect of predicting in advance whether the vehicle lamp is faulty and ensure the stable operation of the switch power supply system.

[0004] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention is as follows:

[0005] A process-oriented vehicle light pre-diagnosis method comprises the following steps:

[0006] Step S1. Calibrate the standard value of the sampling period of the chip of the sampled vehicle lamp;

[0007] Step S2. Sampling the chip of the non-faulty headlight to obtain the headlight operation data, until the headlight operation data of n vehicle ignition cycles are sampled, then entering step S3;

[0008] Step S3. Obtaining the change trend of the headlight operation data of the non-faulty headlights according to the sampled headlight operation data of n vehicle ignition cycles;

[0009] Step S4. During the use of the headlight, detect whether the chip of the headlight generates a level fault signal. If so, proceed to step S5; if not, monitor and sample the chip data. When the data change trend of the chip does not conform to the change trend of the headlight operation data of the headlight without fault, proceed to step S6.1;

[0010] Step S5. Sample the chip data and determine whether its change trend is consistent with the change trend of the headlight operation data of the non-faulty headlights. If so, proceed to step S6.2; if not, proceed to step S6.3;

[0011] Step S6.1. Issue a headlight maintenance alarm, and proceed to step S6.4;

[0012] Step S6.2. Determine whether the duration of the level fault signal generated by the headlight chip is greater than the standard value of the sampling period. If so, proceed to step S6.3; if not, issue a false alarm of headlight fault and proceed to step S6.4;

[0013] Step S6.3. Issue a headlight failure alarm and proceed to step S6.4.

[0014] Step S6.4. The process ends.

[0015] The process-oriented vehicle lamp pre-diagnosis method of the present invention first calculates the change trend of vehicle lamp operation data of non-faulty vehicle lamps as a historical record, then samples the data of the switching power supply chip during the use of the vehicle lamp and compares it with the historical record, thereby determining whether the vehicle lamp has a fault.

[0016] Preferably, the vehicle light pre-diagnosis method also includes a signal sampling and detection circuit applied to a switching power supply chip of the vehicle light; the signal sampling and detection circuit includes 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 to the controller.

[0017] Preferably, the signal sampling and detection circuit further includes 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 to the input end of the detection loop.

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

[0019] Preferably, step S1 includes: calibrating the sampling period standard value of the switching power supply chip to be t typ , the typical voltage value is U typ , the typical current value is I typ , the typical temperature is T typ , boundary value of voltage change trend|K U |, Boundary value of voltage difference change trend|K ΔU |, boundary value of current change trend|K I |, boundary value of current difference change trend|K ΔI |, Boundary value of temperature change trend|K T |, Boundary value of temperature difference change trend|K ΔT |.

[0020] Preferably, step S2 includes: sampling the voltage, current, and temperature of the switch power supply chip of the non-faulty headlights of the vehicle ignition cycle for n times, and calculating the average value of the voltage sampled 1 to n-1 times. Average value of current Average temperature And calculate the average value of the voltage difference The average value of the current difference The average of the temperature difference The calculation formula for calculating the average voltage is as follows:

[0021] Where n≥2;

[0022] or Where n=1.

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

[0024] Where n≥1;

[0025] Where n≥2.

[0026] Preferably, step S4 comprises:

[0027] Step S4.1. If it is detected that the switch power chip of the headlight does not generate a level fault signal, the voltage, current and temperature of the switch power chip 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;

[0028] Step S4.2. Determine whether K1≥|KU| and K2≥|KΔU|. If so, determine that the headlight is not faulty and proceed to step S6.4. If not, proceed to step S4.3.

[0029] Step S4.3. Determine whether K3≥|KI| and K4≥|KΔI|. If so, determine that the headlight is not faulty and proceed to step S6.4. If not, proceed to step S4.4.;

[0030] Step S4.4. Determine whether K5≥|KT| and K6≥|KΔT|. If so, determine that the vehicle light is not faulty and proceed to step S6.4. If not, determine that the vehicle light is faulty and proceed to step S6.1.

[0031] Preferably, step S5 comprises:

[0032] Step S5.1. Sample the voltage, current and temperature of the switching power supply chip and calculate the corresponding voltage change trend K7, voltage difference change trend K8, current change trend K9, current difference change trend K 10 、Temperature change trend K 11 , Temperature difference change trend K 12 ;

[0033] Step S5.2. Determine whether K7≥|KU| and K8≥|KΔU|, if so, proceed to step S6.3, if not, proceed to step S5.3;

[0034] Step S5.3. Determine whether K9≥|KI| and K10≥|KΔI|, if so, proceed to step S6.3, if not, proceed to step S5.4;

[0035] Step S5.4. Determine whether K11 ≥ |KT| and K12 ≥ ​​|KΔT|. If so, proceed to step S6.3; if not, proceed to 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 the process returns to step S5.1.

[0037] Beneficial effects:

[0038] The process-oriented vehicle lamp pre-diagnosis method of the present invention first calculates the change trend of vehicle lamp operation data of non-faulty vehicle lamps as a historical record, then samples the data of the switching power supply chip during the use of the vehicle lamp and compares it with the historical record, thereby determining whether the vehicle lamp has a fault. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 Shown is a flow chart of a process-oriented vehicle light pre-diagnosis method according to an embodiment;

[0040] Figure 2 Shown is a schematic diagram of a signal sampling and detection circuit of an embodiment;

[0041] Figure 3 Shown is a first timing diagram of a process-oriented vehicle light pre-diagnosis method according to an embodiment;

[0042] Figure 4 Shown is a second timing diagram of a process-oriented vehicle light pre-diagnosis method according to an embodiment.

[0043] Reference numerals

[0044] 101, power supply device; 102, input signal; 200, switching power supply chip; 201, FAULT pin; 300, controller; 400, detection circuit. DETAILED DESCRIPTION

[0045] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

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

[0047] Example

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

[0049] Step S1. Calibrate the standard value of the sampling period of the chip of the sampled vehicle lamp;

[0050] Step S2. Sampling the chip of the non-faulty headlight to obtain the headlight operation data, until the headlight operation data of n vehicle ignition cycles are sampled, then entering step S3;

[0051] Step S3. Obtaining the change trend of the headlight operation data of the non-faulty headlights according to the sampled headlight operation data of n vehicle ignition cycles;

[0052] Step S4. During the use of the headlight, detect whether the chip of the headlight generates a level fault signal. If so, proceed to step S5; if not, monitor and sample the chip data. When the data change trend of the chip does not conform to the change trend of the headlight operation data of the headlight without fault, proceed to step S6.1;

[0053] Step S5. Sample the chip data and determine whether its change trend is consistent with the change trend of the headlight operation data of the non-faulty headlights. If so, proceed to step S6.2; if not, 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 headlight chip is greater than the standard value of the sampling period. If so, proceed to step S6.3; if not, issue a false alarm of headlight fault and proceed to step S6.4;

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

[0057] Step S6.4. The process ends.

[0058] Preferably, the vehicle light pre-diagnosis method also includes a signal sampling and detection circuit for a switching power supply chip 200 applied to the vehicle light; 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; and the output end 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 ; and the input signal 102 is connected to the input end of the detection loop 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, the step S1 includes: calibrating the typical value of the sampling period of the switching power supply chip 200 to be t typ , the typical voltage value is U typ , the typical current value is I typ , the typical temperature is T typ , boundary value of voltage change trend|K U |, Boundary value of voltage difference change trend|K ΔU |, boundary value of current change trend|K I |, boundary value of current difference change trend|K ΔI |, Boundary value of temperature change trend|K T |, Boundary value of temperature difference change trend|K ΔT |.

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

[0063] Where n≥2;

[0064] or Where n=1.

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

[0066] Where n≥1;

[0067] Where n≥2.

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

[0069] Preferably, step S4 comprises:

[0070] Step S4.1. If it is detected that the switch power chip 200 of the headlight does not generate a level fault signal, the voltage, current and temperature of the switch power 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 so, determine that the headlight is not faulty and proceed to step S6.4. If not, proceed to step S4.3.

[0072] Step S4.3. Determine whether K3≥|KI| and K4≥|KΔI|. If so, determine that the headlight is not faulty and proceed to step S6.4. If not, proceed to step S4.4.;

[0073] Step S4.4. Determine whether K5≥|KT| and K6≥|KΔT|. If so, determine that the vehicle light is not faulty and proceed to step S6.4. If not, determine that the vehicle light is faulty and proceed to step S6.1.

[0074] Preferably, step S5 comprises:

[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 K 10 、Temperature change trend K 11 , Temperature difference change trend K 12 ;

[0076] Step S5.2. Determine whether K7 ≥ |KU| and K8 ≥ |KΔU|, if so, proceed to step S6.3, if not, proceed to step S5.3;

[0077] Step S5.3. Determine whether K9≥|KI| and K10≥|KΔI|, if so, proceed to step S6.3, if not, proceed to step S5.4;

[0078] Step S5.4. Determine whether K11 ≥ |KT| and K12 ≥ ​​|KΔT|. If so, proceed to step S6.3; if not, proceed to step S6.2.

[0079] 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 200 can be adjusted and the process returns to step S5.1.

[0080] Furthermore, when at least one of the judgment results in step S5.2 is "yes", it is necessary to re-sample and judge again. If at least one of the judgment results is still "yes", it means that the car light has indeed failed and a fault feedback information should be issued. Otherwise, the sampling algorithm of the switching power supply chip 200 should be adjusted (the sampling points are doubled and the sampling period is doubled).

[0081] Furthermore, if a 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 interfered with or have a logical error, resulting in a false alarm, and the fault reminder is canceled.

[0082] Furthermore, when it is determined in step S6.2 that the duration of the level fault signal generated by the chip of the vehicle lamp is less than a set time threshold, it is determined that the vehicle lamp fault is a false alarm.

[0083] Specifically, in the signal sampling and detection circuit of this embodiment, the controller 300 obtains the level signal of the FAULT pin 201 of the switching power supply chip 200. When the FAULT pin ≠1, the switching power supply chip 200 does not generate a level fault signal. When the FAULT pin = 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 operation of the switching power supply chip 200, and detects the input signal 102 through the detection circuit 400 to control whether to output the LED light of the car light (all the LED lights of the car light 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, and at the same time reminds the FAULT pin 201 according to the status of the switching power supply chip 200 to detect whether it is working normally.

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

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

[0087] Specifically, the process-oriented vehicle light pre-diagnosis method of this embodiment can judge the failure trend of the chip by sampling the voltage, current and temperature of the switching power supply chip 200 and comparing them with historical data, thereby achieving the effect of predicting chip failure in advance or reducing misjudgment.

[0088] Specifically, the process-oriented vehicle lamp pre-diagnosis method of this embodiment samples voltage and current parameters when the switching power supply is started, monitors temperature changes, adjusts the sampling period, etc., and continuously records and adjusts relevant parameters during the operation of the vehicle lamp to achieve the purpose of predicting the trend of fault occurrence and reducing the probability of misjudgment of faults.

[0089] Specifically, the process-oriented pre-diagnosis method for vehicle lights of the present embodiment performs step-by-step calculation and comparison on the input and output states of the switching power supply chip 200 and reads the internal states (temperature, voltage characteristics) therein with historical records each time the vehicle lights are started, and then updates the quality judgment parameters of the switching power supply chip 200 in real time, and makes a fault trend judgment on the vehicle light switching power supply with single-level fault feedback (error state output reminder FAULT signal), so as to achieve the effect of predicting failure in advance or reducing the probability of false alarm, thereby ensuring the stable operation of the switching power supply system.

[0090] The present 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, the software strategy of calculating numerical trends through parameters such as voltage, current, temperature, or comparing with historical values, or the algorithm of similar pre-diagnosis strategy should all be within the protection scope of the present invention.

[0092] The above is a detailed description of an embodiment of a process-oriented vehicle light pre-diagnosis method provided by the present invention. This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the core idea of ​​the present invention. It should be pointed out that for ordinary technicians in this technical field, without departing from the principle of the present invention, the present invention can also be improved and modified, and these improvements and modifications also fall within the scope of protection of the claims of the present invention.

Claims

1. A process-oriented vehicle light pre-diagnosis method, characterized in that: The following steps are involved: Step S1. Calibrate the standard value of the sampling period of the chip of the sampled vehicle lamp; Step S2. Sampling the chip of the non-faulty headlight to obtain the headlight operation data, until the headlight operation data of n vehicle ignition cycles are sampled, then entering step S3; Step S3. Obtaining the change trend of the headlight operation data of the non-faulty headlights according to the sampled headlight operation data of n vehicle ignition cycles; Step S4. During the use of the lamp, detect whether the lamp chip generates a level fault signal. If so, proceed to step S5; If not, the chip data is monitored and sampled, and when the chip data change trend is not consistent with the change trend of the lamp operation data of the non-faulty lamp, step S6.1 is entered; Step S5. Sample the chip data and determine whether its change trend is consistent with the change trend of the headlight operation data of the non-faulty headlights. If so, proceed to step S6.2; if not, 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 headlight chip is greater than the standard value of the sampling period. If so, proceed to step S6.3; if not, issue a false alarm of headlight fault and proceed to step S6.4; Step S6.

3. Issue a headlight failure alarm and proceed to step S6.

4. Step S6.

4. The process ends.

2. The process-oriented vehicle light pre-diagnosis method according to claim 1, characterized in that: The vehicle lamp pre-diagnosis method further comprises a signal sampling and detection circuit applied to a switch power supply chip (200) of the vehicle lamp; the signal sampling and detection circuit comprises a controller (300) and a detection circuit (400); the controller (300) communicates with the switch power supply chip (200); and the output end of the detection circuit (400) is connected to the controller (300).

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

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

5. The process-oriented vehicle light pre-diagnosis method according to claim 2, characterized in that: The step S1 comprises: calibrating the sampling period standard value of the switching power supply chip (200) to be t typ , the typical voltage value is U typ , the typical current value is I typ , the typical temperature is T typ , boundary value of voltage change trend|K U |, Boundary value of voltage difference change trend|K ΔU |, boundary value of current change trend|K I |, boundary value of current difference change trend|K ΔI |, Boundary value of temperature change trend|K T |, Boundary value of temperature difference change trend|K Δτ |.

6. The process-oriented vehicle light pre-diagnosis method according to claim 5, characterized in that: The step S2 comprises: sampling the voltage, current and temperature of the switch power supply chip (200) of the non-faulty headlights of n vehicle ignition cycles, and calculating the average value of the voltage sampled 1 to n-1 times. Average value of current Average temperature And calculate the average value of the voltage difference The average value of the current difference The average of the temperature difference The calculation formula for calculating the average voltage is as follows: Where n≥2; or Where n=1.

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

8. The process-oriented vehicle light pre-diagnosis method according to claim 7, characterized in that: The step S4 comprises: Step S4.

1. If it is detected that the switch power chip (200) of the headlight does not generate a level fault signal, the voltage, current and temperature of the switch power 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, it is determined that the headlight is not faulty and the process goes to step S6.4, if no, it goes to step S4.3; Step S4.

3. Determine whether K3≥|K I | and K4≥|K ΔI |, if yes, it is determined that the headlight is not faulty and the process goes to step S6.4, if no, it goes to step S4.4.; Step S4.

4. Determine whether K5 ≥ |K T | and K6≥|K ΔT |, if so, it is determined that the headlight is not faulty and the process goes to step S6.4, if not, it is determined that the headlight is faulty and the process goes to step S6.

1.

9. The process-oriented vehicle light pre-diagnosis method according to claim 8, characterized in that: The step S5 comprises: 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, current difference change trend K 10 、Temperature change trend K 11 , Temperature difference change trend K 12 ; Step S5.

2. Determine whether K7≥|K U | and K8≥|K ΔU |, if yes, proceed to step S6.3, if no, proceed to step S5.3; Step S5.

3. Determine whether K9 ≥ |K I | and K 10 ≥|K ΔI |, if yes, proceed to step S6.3, if no, proceed to step S5.4; Step S5.

4. Determine whether K 11 ≥|K T | and K 12 ≥|K ΔT |, if yes, go to step S6.3, if no, go to step S6.

2.

10. The process-oriented vehicle light pre-diagnosis method according to claim 9, characterized in that: The step S5.2 further includes: when it is determined that K7≥|K U | and K8≥|K ΔU |, the sampling point and sampling period of the switching power supply chip (200) can be adjusted and the process returns to step S5.1.

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