With Navigation

DTC Troubleshooting: B1780

DTC B1780: HandsFreeLink steering wheel switch line short (with navigation)

Check the vehicle battery condition first 12 Volt Battery Test.

1. Turn the ignition switch to LOCK (0), then start the engine, and turn the steering wheel from lock to lock several times.

2. Do the HFL Self-Diagnostic Function, and check for HFL DTCs.

Is DTC B1780 indicated?

YES -

Go to step 3.

NO -

Intermittent failure, the system is OK at this time.

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

4. Do the HFL switch test.

Is the switch OK?

YES -

Go to step 5.

NO -

Replace the HFL-navigation voice control switch Voice Control Switch Replacement.

5. Disconnect the HandsFreeLink control unit 32P connector.

6. Disconnect the HFL-navigation voice control switch 5P connector, then reconnect the cable reel subharness 20P connector.

7. Check for continuity between HandsFreeLink control unit 32P connector terminal No. 2 and body ground.





Is there continuity?

YES -

Repair a short to body ground in the wire between the HandsFreeLink control unit, the cable reel, and the HFL-navigation voice control switch. If the wire is OK, substitute a known-good cable reel Service and Repair, and recheck. If the symptom/indication goes away, replace the original cable reel Service and Repair.

NO -

Replace the HandsFreeLink control unit.