Materials:
* Multimeter
* Test lamp
* Insulation tape
* Wires for jumpers (if necessary)
Precautions:
* Before starting work, disconnect the negative terminal of the battery.
* Wear protective gloves and goggles.
* Be careful when working with electrical wires.
Procedure:
1. Check the battery. Connect the multimeter to the battery terminals: the red probe to the positive terminal, and the black probe to the negative terminal. The voltage should be in the range of 12-13 volts.
2. Check fuses. Open the fuse box and inspect the fuses. Replace any blown fuses.
3. Check the relay. Find the relay responsible for the circuit being tested. Use a test light to check for voltage at the relay contacts. If no voltage is detected, replace the relay.
4. Check the switches. Set the multimeter to measure resistance. Remove the cap from the switch and touch the multimeter probes to the switch contacts. When the switch is turned on, the resistance should be low (close to zero). If resistance is high, replace switch.
5. Check wiring. Use a multimeter and test light to check wiring continuity. Set the multimeter to measure resistance and touch the probes to both ends of the wire being tested. Resistance should be low. If the resistance is high, check for breaks or shorts in the wire.
6. Check grounding points. Locate the grounding points and check if there is good metal-to-metal contact between them and the vehicle body. If contact is poor, clean surfaces and tighten bolts.
Adviсe:
* Use the vehicle wiring diagram to determine the location of components and wiring.
* Disconnect and connect wires only with the ignition off.
*If you discover a problem that you cannot repair, contact a qualified mechanic for assistance.