Car electrical diagnostics
1. Visual inspection:
* Check the condition of all electrical connectors, wires and fuses.
* Look for signs of corrosion, damage or loose connections.
* Make sure all wires are securely fastened and not frayed.
2. Battery testing:
* Check the battery voltage using a multimeter.
* Start the engine and check the voltage again. It should be at least 13.5 volts with the engine running.
* Perform a load test on the battery to determine its capacity and starting ability.
3. Checking the charging system:
* Check the generator output voltage using a multimeter.
* Start the engine and let it idle. The voltage should be in the range of 13.8-15.2 volts.
*If the voltage is too low or too high, further diagnosis of the generator is necessary.
4. Checking the lighting system:
* Check all headlights, turn signals, brake lights and parking lights.
*If any of them do not work, check the corresponding fuses and bulbs.
* Check lighting system switches and contacts for opens or poor connections.
5. Checking the starting system:
* Check the condition of the starter and connecting wires.
* Try to start the engine. If the starter does not turn over or turns over slowly, it may need testing or replacement.
* Check the condition of the starter relay and wiring.
6. Checking the engine management system (ECM):
*Use a code scanner to look for any stored trouble codes (DTCs).
* Read the DTCs and perform the appropriate diagnostic procedures.
* Check electrical connections between the ECM and sensors, actuators and other components.
7. Other electrical systems:
* Check the operation of the windows, door locks and power seats.
* Analyze any irregularities or failures in the operation of these systems.
* Check wiring, switches and modules associated with these systems.
Tools and equipment required for diagnosis:
* Multimeter
* Code scanner
*Battery Load Tester
* Dielectric grease
* Ammeter clamp