B1779

DTC Troubleshooting: B1779

DTC B1779:

HandsFreeLink steering wheel switch line short

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN System Diagnosis Test Mode A Troubleshooting - B-CAN System Diagnosis Test Mode A.

1. Connect the HDS to the DLC Initial Inspection and Diagnostic Overview.

2. Clear the DTCs with the HDS.

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

4. Check for DTCs with the HDS.

Is DTC B1779 indicated?

YES -

Go to step 5.

NO -

Intermittent failure, the system is OK at this time.�

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

6. Do the HFL switch test HFL Switch Test.

Is the switch OK?

YES -

Go to step 7.

NO -

Replace the HFL-navigation voice control switch Service and Repair.�

7. Disconnect the HandsFreeLink control unit 28P connector.

8. Disconnect the HFL-navigation voice control switch 5P connector, then connect the cable reel 20P connector.

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

10. Measure the voltage between HFL-navigation voice control switch 5P connector terminal No. 3 and body ground.





Is there voltage?

YES -

Go to step 13.

NO -

Go to step 11.

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

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





Is there continuity?

YES -

Go to step 15.

NO -

Repair an open in the wire between the switch, the cable reel, and the HandsFreeLink control unit.�

13. Disconnect the cable reel 20P connector.

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





Is there voltage?

YES -

Repair a short to power in the wire between the HandsFreeLink control unit and the cable reel.�

NO -

Replace the cable reel Service and Repair.�

15. Disconnect the audio-navigation unit connector A (24P).

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





Is there continuity?

YES -

Replace the HandsFreeLink control unit Service and Repair.�

NO -

Go to step 17.

17. Substitute a known-good cable reel, and check for continuity between HFL-navigation voice control switch 5P connector terminal No. 4 and audio-navigation unit connector A (24P) terminal No. 5.





Is there continuity?

YES -

Replace the original cable reel Service and Repair.�

NO -

Repair an open in the wire between the audio remote, the HFL voice control switch, and the audio-navigation unit.�