B2981

DTC Troubleshooting: B2981 (NAVI communication error)

DTC B2981 or NAVI communication error is indicated:

Climate Control Unit Lost Communication with Navigation System

1. Clear the DTC with the HDS.

2. Turn the ignition switch to LOCK (0), and then back to ON (II).

3. Do the self-diagnostic with the HDS or the climate control unit.

4. Check for DTCs.

Is DTC B2981 or NAVI communication error indicated?

YES -

Go to step 5.

NO -

Intermittent failure. Check for loose wires or poor connections on the navigation unit and climate control unit circuit.

5. Turn the ignition switch to LOCK (0).

6. Disconnect navigation unit connector B (32P).

7. Disconnect the climate control unit 40P connector.

8. Check for continuity between the following terminals of the climate control unit 40P connector and navigation unit connector B (32P).









Is there continuity?

YES -

Go to step 9.

NO -

Repair an open in the wire(s) between the climate control unit and the navigation unit.

9. Check for continuity between body ground and climate control unit 40P connector terminals No. 6, No. 7, and No. 8 individually.





Is there continuity?

YES -

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

NO -

Go to step 10.

10. Check for continuity between the climate control unit 40P connector terminals as follows.





Is there continuity between any of the terminals?

YES -

Repair a short in the wires between the climate control unit and the navigation unit.

NO -

Check for loose wires or poor connections at the climate control unit 40P connector and at navigation unit connector B (32P). If the connections are good, substitute a known-good climate control unit, and recheck. If the symptom/indication goes away, replace the original climate control unit Climate Control Unit Removal/Installation. If the symptom/indication continues, substitute a known-good navigation unit, and recheck. If the symptom/indication goes away, replace the original navigation unit.