Audio Unit Button Illumination Does Not Work

Audio System Symptom Troubleshooting - Audio unit button illumination does not work

Audio unit button illumination does not work

NOTE:

- Check the vehicle battery condition first Battery Test.
- Check the connectors for poor connections or loose terminals.
- If the audio unit does not turn on, go to Audio unit power switch will not turn on troubleshooting Audio Unit Power Switch Will Not Turn On (No Information Display and No Sound)

1. Turn the ignition switch to ON (II).

2. Turn on the combination light switch to the parking light position.

3. Check the illumination of the audio unit buttons.

Are the buttons illuminated?

YES -

Intermittent failure, 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. Start by checking the No. 7 (7.5 A) fuse in the passenger's under-dash fuse/relay box. If the fuse is OK, check for an open in the wire between the passenger's under-dash fuse/relay box and the audio unit.

5. Turn the ignition switch to LOCK (0).

6. Disconnect audio unit connector A (20P).

NOTE: Eject all CDs before removing the audio unit and CD changer to prevent damaging the CD player's load mechanism.

7. Disconnect gauge control module connector A (20P).

8. Check for continuity between audio unit connector A (20P) terminal No. 19 and gauge control module connector A (20P) terminal No. 1.





Is there continuity?

YES -

Go to step 9.

NO -

Repair an open in the wire between the gauge control module and the audio unit.

9. Turn the ignition switch to ON (II).

10. With the combination light switch in the parking light position still on, measure the voltage between audio unit connector A (20P) terminal No. 9 and body ground.





Is there battery voltage?

YES -

Check the connection at audio unit connector A (20P). If the connection OK, Substitute a known-good audio unit Audio Unit Removal / Installation, and recheck. If the symptom/indication goes away, replace the original audio unit Audio Unit Removal / Installation.

NO -

Check the No. 7 (7.5 A) fuse in the passenger's under-dash fuse/relay box. repair an open in the wire between the passenger's under-dash fuse/relay box and the audio unit.