Information Bus: Testing and Inspection

Communication Line Circuit Troubleshooting (With Navigation System)

1. Disconnect navigation display unit connector A (5P).
2. Disconnect climate control unit connector B (20P).




3. Check for continuity between the following terminals of climate control unit connector B (20P) and navigation display unit connector A (5P).
20P 5P
No. 8 No. 2
No. 12 No. 4
No. 14 No. 3

Is there continuity?

YES - Go to step 4.

NO - Repair any open in the wire(s) between the climate control unit and the navigation display unit.




4. Check for continuity between the body ground and climate control unit connector B (20P) terminals No. 8, 12 and 14 individually.

Is there continuity?

YES - Repair any short to body ground in the wire(s) between the climate control unit and the navigation display unit.

NO - Check for loose wires or poor connections at climate control unit connector B (20P) and at navigation display unit connector A (5P). If the connections are good, substitute a known-good climate control unit. If the problem still exists, replace the navigation display unit.