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

NOTE: 

• Check the vehicle 12 volt battery condition first .
• Check for B-CAN DTCs and resolve them before troubleshooting.
• Check the connectors for poor connections or loose terminals.

1. Problem verification:

   - 1. Turn the vehicle to the ON mode.

   - 2. Turn the combination light switch to the parking light ( ) position

   - 3. Check the illumination of the audio-navigation unit buttons.

   Are the buttons illuminated?

   YES 

   Intermittent failure, the audio unit is OK at this time.

   NO 

   The failure is duplicated, go to step 2.

2. Determine possible failure area (interior lights circuit, others):

   Check the illumination of several other buttons not related to the audio/navigation system.

   Are the buttons illuminated?

   YES 

   Go to step 3.

   NO 

   Troubleshoot the interior lights.

3. Determine possible failure area (audio-navigation unit, others):

   Go into the System Diagnostic Mode, and use the Vehicle Status to check the ILLUMI signal .

   Does the ILL signal change from [0] to [1] when the combination light switch is turned to the parking light position?

   YES 

   Replace the audio-navigation unit .

   NO 

   Go to step 4.

4. Open wire check (B-CAN_H line, B-CAN_L line):

   - 1. Turn the combination light switch off.

   - 2. Turn the vehicle to the OFF (LOCK) mode.

   - 3. Disconnect the following connectors.

   Gauge control module 32P connector

   Audio-navigation unit connector B (20P)

   - 4. Check for continuity between test points 1 and 2.

   Test condition	Vehicle OFF (LOCK) mode
   	Gauge control module 32P connector: disconnected
   	Audio-navigation unit connector B (20P): disconnected
   Test point 1	Gauge control module 32P connector No. 23. Refer to GAUGE CONTROL MODULE CONNECTOR FOR INPUTS AND OUTPUTS(NA)
   Test point 2	Audio-navigation unit connector B (20P) No. 13

   Test point 1	Gauge control module 32P connector No. 24. Refer to GAUGE CONTROL MODULE CONNECTOR FOR INPUTS AND OUTPUTS(NA)
   Test point 2	Audio-navigation unit connector B (20P) No. 3

   Is there continuity?

   YES 

   Replace the audio-navigation unit .

   NO 

   Repair an open in the wire(s) between the audio-navigation unit and the gauge control module.