Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
DTC B1779: HFL Switch or Voice Control Switch (HFL TALK/HFL BACK Buttons) Circuit Open/Short to Power
- Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
- Clear the DTCs with the HDS.
- Turn the ignition switch to LOCK (0), then start the vehicle and turn the steering wheel back and forth several times.
- 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.
- Turn the ignition switch to LOCK (0).
- Do the HFL switch test (see
HFL SWITCH TEST ).
Is the switch OK?
YES -Go to step 7.
NO -Replace the HFL-navigation voice control switch (see VOICE CONTROL SWITCH REPLACEMENT - ('10 MODEL) ).
- Disconnect the HandsFreeLink control unit 28P connector.
- Disconnect the HFL-navigation voice control switch 5P connector, then connect the cable reel 20P connector.
- Turn the ignition switch to ON (II).
- Measure the voltage between HFL-navigation voice control switch 5P connector terminal No. 3 and body ground.Fig 1: Measuring Voltage Between HFL-Navigation Voice Control Switch 5P Connector Terminal No. 3 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there voltage?
YES -Go to step 13.
NO -Go to step 11.
- Turn the ignition switch to LOCK (0).
- Check for continuity between HandsFreeLink control unit 28P connector terminal No. 2 and HFL-navigation voice control switch 5P connector terminal No. 3.Fig 2: Checking Continuity Between Handsfreelink Control Unit 28P Connector Terminal No. 2 And HFL-Navigation Voice Control Switch 5P Connector Terminal No. 3
Courtesy of AMERICAN HONDA MOTOR CO., INC.
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.
- Disconnect the cable reel 20P connector.
- Measure the voltage between HandsFreeLink control unit 28P connector terminal No. 2 and body ground.Fig 3: Measuring Voltage Between Handsfreelink Control Unit 28P Connector Terminal No. 2 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.
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 (see CABLE REEL REPLACEMENT ).
- Disconnect audio-navigation unit connector A (24P).
- Check for continuity between HFL-navigation voice control switch 5P connector terminal No. 4 and audio-navigation unit connector A (24P) terminal No. 5.Fig 4: Checking Continuity Between HFL-Navigation Voice Control Switch 5P Connector Terminal No. 4 And Audio-Navigation Unit Connector A (24P) Terminal No. 5
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Replace the HandsFreeLink control unit (see CONTROL UNIT INPUT TEST/REPLACEMENT ).
NO -Go to step 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.Fig 5: Checking Continuity Between HFL-Navigation Voice Control Switch 5P Connector Terminal No. 4 And Audio-Navigation Unit Connector A (24P) Terminal No. 5
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Is there continuity?
YES -Replace the original cable reel (see CABLE REEL REPLACEMENT ).
NO -Repair an open in the wire between the audio remote, the HFL voice control switch, and the audio-navigation unit.
NO RELATED
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.