B1776

DTC Troubleshooting: B1776

DTC B1776: Microphone Input/Output Short to Ground/Open

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. Clear the DTCs with the HDS.

2. Turn the ignition switch to LOCK (0), and then back to ON (II).

3. Check for DTCs with the HDS.

Is DTC B1776 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. Remove the roof console Service and Repair and the glove box. Service and Repair

6. Disconnect the 20P connector from the roof console and the 28P connector from the HandsFreeLink control unit.

7. Check for continuity between body ground and the terminals No. 13 and No. 14 of the HandsFreeLink control unit 28P connector individually, then between terminals No. 12 and No. 13.

Is there continuity?
YES - Replace the faulty harness between the HandsFreeLinks control unit and the roof console.

NO - Go to step 8.






8. Check for continuity between the terminals shown of the HandsFreeLink control unit 28P connector and the roof console 20P connector.

Is there continuity?
YES - Go to step 9.

NO - Replace the faulty harness between the HandsFreeLink control unit and the roof console.






9. Check if the vehicle is equipped with a navigation system.

Is the vehicle navigation equipped?
YES - Go to step 10.

NO - Substitute a known-good HFL control unit and recheck.


10. Disconnect the 14P connector from the navigation unit.

11. Check for continuity between body ground and the terminals No. 27 and No. 28 of the HandsFreeLink control unit 28P connector individually, then between terminals No. 26 and No. 27.

Is there continuity?
YES - Replace the faulty harness between the HandsFreeLink control unit and the navigation unit.

NO - Go to step 12.






12. Check for continuity between the terminals shown of the HandsFreeLink control unit 28P connector and the navigation unit connector B (14P).

Is there continuity?
YES - Substitute a known-good HandsFreeLink control unit, then recheck. If the symptom goes away, replace the original HandsFreeLink control unit. If the symptom does not go away, replace the faulty navigation unit.

NO - Replace the faulty harness between the HandsFreeLink control unit and the navigation unit.