Display Unit Buttons Do Not Work
Symptom TroubleshootingDisplay unit buttons do not work
NOTE:
- Always check the connectors for poor connections or loose terminals.
- Before troubleshooting, get the navigation system anti-theft codes.
- After troubleshooting, enter the navigation system anti-theft codes.
1. Turn the ignition switch to ACC (I).
2. Measure the voltage between body ground and display unit connector B (20P) terminal No. 1 and No. 2 individually.
Is there battery voltage?
YES - Go to step 3.
NO - If the +B wire does not have voltage, repair the open in the wire between the passenger's under-dash fuse/relay box and the display unit. If the ACC wire does not have voltage, repair the open in the wire between the passenger's under-dash fuse/relay box and the display unit.
3. Turn the ignition switch OFF.
4. Disconnect the display unit connector B (20P).
5. Check for continuity between display unit connector B (20P) terminal No. 10 and body ground.
Is there continuity?
YES - Go to step 6.
NO - Repair the open in the wire between the display unit and body ground (G501).
6. Disconnect the navigation unit connector B (16P)
7. Check for continuity between body ground and display unit connector B (20P) terminal No. 5 and No. 15 individually.
Is there continuity?
YES - There is a short to body ground in the circuit between the display unit and the navigation unit Replace the affected shielded harness.
NO - Go to step 8.
8. Check for continuity between display unit connector B (20P) terminal No. 5 and navigation unit connector B (16P) terminal No. 7
Is there continuity?
YES - Go to step 9.
NO - There is an open in the circuit between the display unit and the navigation unit. Check for poor connections or loose terminals at the display and navigation units. If a poor connection or loose terminal is found, replace the affected shielded harness.
9. Check for continuity between display unit connector B (20P) terminal No. 15 and navigation unit 16P connector B(16P) terminal No.15
Is there continuity?
YES - Replace the display unit.
NO - There is an open in the circuit between the display unit and the navigation unit. Check for poor connections or loose terminals at the display and navigation units If a poor connection or loose terminal is found, replace the affected shielded harness.