Audio Unit Button Illumination Does Not Work
Audio unit button illumination does not work1. Turn the ignition switch to ON (II).
2. Turn the combination lighting switch to the parking light position.
3. Check the illumination of the audio unit buttons.
Are the buttons illuminated?
YES - Intermittent problem; the audio unit is OK at this time. Check for loose or poor connections at audio unit connector A (20P).
NO - Go to step 4.
4. Check the illumination of several other buttons not related to the audio system.
Are the buttons illuminated?
YES - Go to step 5.
NO - Troubleshoot the interior lights.
5. Turn the ignition switch OFF.
6. Disconnect audio unit connector A (20P).
7. Disconnect the gauge control module connector B (18P).
8. Check for continuity between audio unit connector A (20P) terminal No. 19 and gauge control module connector B (18P) terminal No.9.
Is there continuity?
YES - Go to step 9.
NO - Repair open in the wire between the gauge control module and the audio unit.
9. Turn the ignition switch to ON (II).
10. With the headlight switch still on, measure the voltage between audio unit connector A (20P) terminal No. 9 and body ground.
Is there battery voltage?
YES - Check the connections at the audio unit connector A (20P). If all connections are OK, replace the audio unit.
NO - Repair open in the wire between the relay control module and the audio unit.