HFL Switch or Voice Control Switch (HFL Talk/HFL Back Buttons) Circuit Open/Short to Power (Without Navigation)

DTC Troubleshooting: B1779

DTC B1779: HFL Switch or Voice Control Switch (HFL TALK/HFL BACK Buttons) Circuit Open/Short to Power (without navigation)

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), or press the engine start/stop button to select the OFF mode, 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), or press the engine start/stop button to select the OFF mode.

6. Do the HFL switch test. HFL Switch Test

Is the switch OK?
YES - Go to step 7.

NO - Replace the audio remote-HFL switch. Steering Wheel Disassembly/Reassembly


7. Remove the center console panel. Center Console Panel Removal/Installation

8. Disconnect the HandsFreeLink control unit 28P connector. Service and Repair

9. Remove the audio remote-HFL switch Steering Wheel Disassembly/Reassembly and disconnect the 12P connector, then connect the cable reel 20P connector.

10. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

11. Measure the voltage between audio remote-HFL switch 12P connector terminal No. 9 and body ground.

Is there voltage?
YES - Go to step 14.

NO - Go to step 12.






12. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

13. Check for continuity between HandsFreeLink control unit 28P connector terminal No. 2 and audio remote-HFL switch 12P connector terminal No. 9.

Is there continuity?
YES - Go to step 16.

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






14. Disconnect cable reel 20P connector.

15. 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 audio remote-HFL switch.

NO - Replace the cable reel.






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

17. Check for continuity between audio remote-HFL switch 12P connector terminal No. 11 and audio unit connector A (24P) terminal No. 5.

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

NO - Go to step 18.






18. Substitute a known-good cable reel, and check for continuity between audio remote-HFL switch 12P connector terminal No. 11 and audio unit connector A (24P) terminal No. 5.

Is there continuity?
YES - Replace the original cable reel.

NO - Repair open in the wire between the audio remote-HFL switch and the audio unit.