The self-checking methods for automobile electrical system faults mainly include the following:
1. Intuitive diagnosis method: This is the most basic diagnostic method, which mainly relies on human senses (vision, hearing, smell, touch) to judge the fault. For example, the type and location of the fault can be preliminarily judged by observing the working status of the electrical equipment, listening to the sound, smelling the smell, etc.
2. Test light method: This is a commonly used method for diagnosing electrical system faults. The specific operation is to use a car bulb as a test light to check whether the circuit has an open circuit fault. If the test light is on, it means that the circuit is normal; if it is not on, it means that there may be a short circuit fault.
3. Power short-circuit method: This method is mainly used to determine whether there is a short circuit fault in the circuit. The specific operation is to short-circuit a certain section of the circuit with a screwdriver or a wire to see if the instrument pointer swings. If the pointer swings in the negative direction, it means that the ignition switch is damaged.
4. Replacement identification method: This method is mainly used to determine whether a certain electrical equipment is normal. The specific operation is to replace the suspected problematic component with a new component, and then observe the working status of the circuit. If the circuit returns to normal, it means that there is a problem with the original component; if the circuit is still abnormal, it means that the problem is not with this component.
5. Meter diagnosis method: This method is mainly used to determine whether there is a short circuit fault in the circuit. The specific operation is to connect the ammeter in series or in parallel in the charging circuit, and then turn on a load circuit. If the ammeter pointer does not move and the relevant equipment does not work, it means that there is a short circuit fault.
6. Open circuit test connection method: This method is mainly used to determine whether there is a grounding fault in the circuit. The specific operation is to disconnect the circuit suspected of having a grounding fault, and then observe the working status of the circuit. If the working phenomenon changes before and after the circuit is disconnected, it means that there may be a grounding fault.
7. Grounding fire test method: This is a commonly used electrical system fault diagnosis method. The specific operation is to remove a certain wiring head before the electrical equipment, scratch and test the fire with the metal part of the car, and judge the circuit condition by sparks. If there is a spark, it means that the circuit is normal; if there is no spark, it means that there may be a circuit breaker.
The above are several common self-test methods for automotive electrical system faults. It should be noted that although these methods can help us make a preliminary diagnosis of the fault, in actual operation, they need to be used flexibly in combination with specific circumstances. At the same time, for some complex faults, it is best to seek help from professional technicians.
