Audio System Symptom Troubleshooting - Audio unit power will not turn on (No information display and no sound)
Audio unit power will not turn on (No information display and no sound)
NOTE:
Check the vehicle battery condition first.
Check the connectors for poor connections or loose terminals.
1.
Problem verification:

Problem verification
?1.
Turn the vehicle to the ON mode.

?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:

Fuse check
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Check the following fuses.
Fuse
No. A22 (10 A)
Location
Under-hood fuse/relay box

Fuse
No. B37 (7.5 A)
Location
Under-dash fuse/relay box

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. A22 (10 A) fuse and/or the No. B37 (7.5 A) fuse circuits.?
3.
Open wire check (+B AUDIO line):

Open wire check (+B AUDIO line)
?1.
Disconnect the following connector.
NOTE: Eject all the discs before disconnecting the audio unit to prevent damaging the CD player load mechanism.

Audio unit connector A (24P)

?2.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
Audio unit connector A (24P): disconnected
Test point 1
Audio unit connector A (24P) No. 3
Test point 2
Body ground

Is there battery voltage?

     
YES
     
     
     
The +B AUDIO wire is OK. Go to step 4.
     
NO
     
     
     
Repair an open in the wire between the No. A22 (10 A) fuse in the under-hood fuse/relay box and the audio unit.?
4.
Open wire check (ACC line):

Open wire check (ACC line)
?1.
Turn the vehicle to the ON mode.

?2.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle ON mode
 
Audio unit connector A (24P): disconnected
Test point 1
Audio unit connector A (24P) No. 24
Test point 2
Body ground

Is there battery voltage?

     
YES
     
     
     
The ACC wire is OK. Go to step 5.
     
NO
     
     
     
Repair an open in the wire between the No. B37 (7.5 A) fuse in the under-dash fuse/relay box and the audio unit.?
5.
Open wire check (GND line):

Open wire check (GND line)
?1.
Turn the vehicle to the OFF (LOCK) mode.

?2.
Check for continuity between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
 
Audio unit connector A (24P): disconnected
Test point 1
Audio unit connector A (24P) No. 1
Test point 2
Body ground

Is there continuity?

     
YES
     
     
     
The GND wire is OK. Go to step 6.
     
NO
     
     
     
Repair an open or high resistance in the wire between the audio unit and body ground (G505).?
6.
Audio panel check (substitution):

Audio panel check (substitution)
?1.
Substitute a known-good audio panel.

?2.
Reconnect the audio unit connector A (24P), and recheck.

Does the symptom go away?

     
YES
     
     
     
     
NO