B1779
DTC Troubleshooting: B1779
DTC B1779: HFL Switch or Voice Control Switch (HFL TALK/HFL BACK Buttons) Circuit Open/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/Replacement
Is the switch OK?
YES - Go to step 7.
NO - Replace the HFL switch. HFL Switch Test/Replacement
7. Remove the glove box. Glove Box Removal/Installation
8. Disconnect the HandsFreeLink control unit 28P connector.
9. Disconnect the HFL switch 6P connector.
10. Turn the ignition switch ON (II).
11. Measure the voltage between the HFL switch connector terminal No. 5 and body ground.
Is there voltage?
YES - Repair short to power on the PUR wire.
NO - Go to step 12.
12. Check for continuity between the HandsFreeLink control unit 28P connector terminal No. 2 and the HFL switch 6P connector terminal No. 5.
Is there continuity?
YES - Go to step 13.
NO - Repair open in the RED/BLK wire between the HFL switch, cable reel, and the HandsFreeLink control unit.
13. Check for continuity between the HFL switch 6P connector terminal No. 2 and audio unit connector A (20P) terminal No. 11.
Is there continuity?
YES - Check for loose or poor connections at the audio unit, HandsFreeLink control unit, and the HFL switch. If the connections are OK, substitute a known-good HandsFreeLink control unit. If the problem is gone, replace the original HandsFreeLink control unit. Service and Repair
NO - Repair open in the wire between the HFL switch, the cable reel, and the audio unit.
