Diagnostics of vehicle electrical equipment
Target:
Identifying faults in the vehicle’s electrical system and eliminating them.
Tools and Equipment:
* Multimeter
* OBD-II scanner
* Test lamp
* Set of wrenches and screwdrivers
*Car wiring diagram
Diagnostic procedure:
1. Visual inspection:
* Inspect the battery, starter, alternator and other electrical system components for visible damage or corrosion.
* Check the condition of wires, fuses and relays.
2. Battery check:
*Measure the battery voltage using a multimeter. It should be between 12.6 and 13.2 volts with the engine off.
* Perform a load test on the battery to check its ability to deliver current.
3. Checking the charging system:
* Start the engine and measure the voltage at the battery terminals. It should be between 13.5 and 14.5 volts.
* Check the generator output voltage using a multimeter.
* Inspect the generator voltage regulator for malfunctions.
4. Checking the ignition system:
* Check the condition of the spark plugs, ignition wires and ignition distributor.
* Measure the resistance and capacitance of the ignition system.
* Scan the vehicle for trouble codes related to the ignition system.
5. Checking the lighting system:
* Check all lamps and make sure they are working properly.
* Check light switches and relays.
* Check the condition of the wiring harnesses and connectors.
6. Checking the comfort system:
* Check the operation of windows, mirrors, seats and other comfort features.
*Check the fuses and relays associated with these functions.
* Check wiring harnesses and connectors for damage.
7. Checking the CAN bus:
*Use an OBD-II scanner to read CAN bus related trouble codes.
* Check the condition of the CAN bus wiring harnesses and connectors.
* Use an oscilloscope to observe the CAN bus signals.
8. Troubleshooting:
* Once the faulty component is identified, replace or repair it.
* Reset fault codes and make sure the fault is resolved.
Additional tips:
*Refer to the vehicle wiring diagram for exact component locations and wiring.
* Don’t hesitate to seek help from a professional auto electrician if you encounter any diagnostic difficulties.
* Check your vehicle’s electrical system regularly to prevent serious problems from occurring.