- Locate the door switches on all doors.
- Check if they are properly aligned with the door frame and not obstructed.
2. Inspect the wiring:
- Look for any signs of damage or wear on the wiring harness that connects the door switches to the light system.
3. Test the door switch:
- Disconnect the door switch connector and use a multimeter to check for continuity between the switch terminals.
- Replace the switch if it's faulty.
4. Check the door switch relay:
- Consult the vehicle's service manual to identify the location of the courtesy light relay.
- Replace the relay if it's faulty.
5. Check the light bulbs:
- Open the light fixtures and inspect the bulbs for any signs of damage or burnout.
- If necessary, replace the faulty light bulbs.
6. Check the ground connections:
- Ensure that the ground connections for the light fixtures and door switches are clean and tight.
7. Test the light switch:
- Turn the light switch to the "On" and "Auto" positions to verify that the lights work.
8. Check the fuse:
- Locate the fuse that controls the courtesy lights in the fuse box.
- Check if the fuse is blown and replace it if necessary.
9. Check the courtesy light timer module:
- If your vehicle is equipped with a courtesy light timer module, inspect it for any signs of damage or failure.
- Replace the module if it's faulty.