B1779

DTC Troubleshooting: B1779

DTC B1779: HFL Switch (HFL TALK/HFL BACK Buttons) Circuit Open/Short

1. Clear the DTCs with the HDS.

2. Turn the ignition switch to LOCK (0), then start the vehicle and turn the steering wheel back and forth several times.

3. Check for DTCs with the HDS.

Is DTC B1779 indicated?
YES - Go to step 4.

NO - Intermittent failure, the system is OK at this time.


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

5. Do the HFL switch test. HFL Switch Test (With Navigation)

Is the switch OK?
YES - Go to step 6.

NO - Replace the HFL-voice control switch. Service and Repair


6. Disconnect the HandsFreeLink control unit 28P connector.

7. Disconnect the HFL-voice control switch 5P connector.

8. Check for continuity between the HandsFreeLink control unit 28P connector terminal No. 2 and the HFL-voice control switch 5P connector terminal No. 3.

Is there continuity?
YES - Go to step 9.

NO - Repair open in the wire between the switch, cable reel, and the HandsFreeLink control unit.






9. Turn the ignition switch to ON (II).

10. Measure the voltage between HandsFreeLink control unit 28P connector terminal No. 2 and body ground.

Is there voltage?
YES - Repair short to power in the wire between the HandsFreeLink control unit and the HFL-voice control switch.

NO - Go to step 11.






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

12. Disconnect navigation unit connector B (24P).

13. Check for continuity between navigation unit connector A (24P) terminal No. 5 and HFL-voice control switch 5P connector terminal No. 4.

Is there continuity?
YES - Replace the HandsFreeLink control unit. Service and Repair

NO - Repair open in the wire between the switch, cable reel, and the navigation unit .