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Navigation Communication Line Circuit Troubleshooting

Navigation Communication Line Circuit Troubleshooting

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




3. Check for continuity between the given terminals of climate control unit connector A (20P) and navigation unit connector A (20P).

Is there continuity?

YES - Go to step 4.

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




4. Check for continuity between body ground and climate control unit connector A (20P) terminals No. 17, 18 and 19 individually.

Is there continuity?

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

NO - Check for loose wire or poor connections at climate control unit connector A (20P) and at the navigation unit connector A (20P). If the connections are good, substitute a known-good climate control unit and/or navigation unit, and recheck. If the symptom/indication goes away, replace the original climate control unit and/or navigation unit.