Display Unit Buttons Do Not Work
Display unit buttons do not workNOTE:
- 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. Go into the Diagnostic mode and use the "Touch Panel" diagnostic under Monitor Check and, if necessary, the "Display" diagnostic under Unit Check.
Do the buttons work properly?
YES - System is OK.
NO - Go to step 3.
3. 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 4.
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.
4. Turn the ignition switch OFF.
5. Disconnect the display unit connector B (20P).
6. Check for continuity between display unit connector B (20P) terminal No.10 and body ground.
Is there continuity?
YES - Go to step 7.
NO - Repair the open in the wire between the display unit and body ground (G401).
7. Disconnect the navigation unit connector A (20P).
8. 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 9.
9. Check for continuity between display unit connector B (20P) terminal No.5 and navigation unit connector A (20P) terminal No.10.
Is there continuity?
YES - Go to step 10.
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.
10. Check for continuity between display unit connector B (20P) terminal No.15 and navigation unit connector A (20P) terminal No.20.
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.