Audio Unit Power Switch Will Not Turn On (No Information Display And No Sound)

Audio System Symptom Troubleshooting - Audio unit power switch will not turn on (No information display and no sound)

Audio unit power switch will not turn on (No information display and no sound)

NOTE:
* Check the vehicle battery condition first Component Tests and General Diagnostics.
* Check the connectors for poor connections or loose terminals.

1. Problem verification:

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

-2. Press the POWER button on to see if the audio unit turns on.

Does the audio system operate properly, and does the audio sound normal?
-YES- Intermittent failure, the system is OK at this time.
-NO- The failure is duplicated, go to step 2.

2. Fuse check:

-1. Turn the ignition switch to LOCK (0).

-2. Check the following fuses.










Are the fuses OK?
-YES- Go to step 3.
-NO- Replace the fuse(s), and recheck. If the fuse(s) blows again, check for a short in the No. B19 (7.5 A) fuse and/or the No. B25 (10 A) fuse circuit(s).

3. Open wire check (+B AUDIO line, ACC line):

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

-2. Measure the voltage between test points 1 and 2.














Is there battery voltage?
-YES- The +B AUDIO and the ACC wires are OK. Go to step 4.
-NO- Repair an open or high resistance in the wire(s) between the No. B19 (7.5 A) fuse in the under-dash fuse/relay box and/or the No. B25 (10 A) fuse in the under-dash fuse/relay box and the audio unit.

4. Open wire check (GND line):

-1. Measure the voltage between test points 1 and 2.










Is there less than 0.2 V?
-YES- The GND wire is OK. Go to step 5.
-NO- Repair an open or high resistance in the wire between the audio unit and body ground (G503).

5. Audio unit check:

-1. Turn the ignition switch to LOCK (0).

-2. Substitute a known-good audio switch panel Audio Unit Removal and Installation, and recheck.

Does the symptom go away?
-YES- Replace the original audio switch panel.
-NO- Replace the audio unit Audio Unit Removal and Installation.