Navigation System Symptom Troubleshooting - Audio-navigation unit will not turn on (No information display and no sound)
Audio-navigation unit will not turn on (No information display and no sound)
NOTE:
Check the vehicle 12 volt battery condition first.
Check if the Day/Night (enu_1740914_1.0) button has been pressed, and turned off the display (see the Owner's Manual for more information).
Check the connectors for poor connections or loose terminals.
1.
Problem verification:

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

?2.
Check if the audio-navigation unit display indicates any information.

Is any information displayed?

     
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. A29 (10 A)
Location
Under-hood fuse/relay box

Fuse
No. B19 (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. A29 (10 A) fuse and/or the No. B19 (7.5 A) fuse circuits.?
3.
Open wire check (+B BACK UP line):

Open wire check (+B BACK UP line)
?1.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle OFF (LOCK) mode
   
Test point 1
Audio-navigation unit connector A (24P) No. 3
Test point 2
Body ground

Is there battery voltage?

     
YES
     
     
     
The +B BACK UP wire is OK. Go to step 4.
     
NO
     
     
     
Repair an open in the wire between the No. A29 (10 A) fuse in the under-hood fuse/relay box and the audio-navigation 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-navigation unit connector A (24P): disconnected
Test point 1
Audio-navigation unit connector A (24P) No. 24
Test point 2
Body ground

Is there battery voltage?

     
YES
     
     
     
The GND wire is OK. Go to step 5.
     
NO
     
     
     
Repair an open in the wire between the No. B19 (7.5 A) fuse in the under-dash fuse/relay box and the audio-navigation unit.?
5.
Open wire check (GND line):

Open wire check (GND line)
?1.
Measure the voltage between test points 1 and 2.
Test condition
Vehicle ON mode
   
Test point 1
Audio-navigation unit connector A (24P) No. 1
Test point 2
Body ground

Is there less than 0.2 V?

     
YES
     
     
     
     
NO
     
     
     
Repair an open in the wire between the audio-navigation unit and body ground (G503).?