DTC B1776: Microphone Input Short to Ground or Microphone Failure

WARNING: This page is about a different car, the 2011 Honda Insight and 2010 Honda Insight. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: If you are troubleshooting multiple DTCs, be sure to follow the instructions in B-CAN system diagnosis test mode A (see TROUBLESHOOTING - B-CAN SYSTEM DIAGNOSIS TEST MODE A ).

Connect the HDS to the DLC (see GENERAL TROUBLESHOOTING INFORMATION ).
Clear the DTCs with the HDS.
Turn the ignition switch to LOCK (0) and then back to ON (II).
Check for DTCs with the HDS.
Is DTC B1776 indicated?

YES -Go to Step 5.

NO -Intermittent failure, the system is OK at this time.
Turn the ignition switch to LOCK (0).
Disconnect the HFL-navigation microphone 3P connector.
Disconnect the HandsFreeLink control unit 28P connector.
Check for continuity between body ground and HandsFreeLink control unit 28P connector terminals No. 13 and No. 14 individually, then between terminals No. 12 and No. 13.

Fig 1: Checking Continuity Between Body Ground And HandsFreeLink Control Unit 28P Connector Terminals
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -There is a short in the wires between the HandsFreeLink control unit and the HFL-navigation microphone. Replace the affected shielded harness.

NO -Go to Step 9.
Check for continuity between the terminals shown of the HandsFreeLink control unit 28P connector and the HFL-navigation microphone 3P connector.

Fig 2: Checking Continuity Between Terminals Of HandsFreeLink Control Unit 28P Connector And HFL-Navigation Microphone 3P Connector
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Go to Step 10.

NO -There is an open in the wire between the HandsFreeLink control unit and the HFL-navigation microphone. Replace the affected shielded harness.
Remove the audio-navigation unit (see AUDIO-NAVIGATION UNIT REMOVAL/INSTALLATION ), and disconnect audio-navigation unit connector D (12P).
Check for continuity between body ground and HandsFreeLink control unit 28P connector terminals No. 27 and No. 28 individually.

Fig 3: Checking Continuity Between Body Ground And HandsFreeLink Control Unit 28P Connector Terminals
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -There is a short to body ground in the wires between the HandsFreeLink control unit and the audio-navigation unit. Replace the affected shielded harness.

NO -Go to Step 12.
Check for continuity between the terminals shown of the HandsFreeLink control unit 28P connector and the audio-navigation unit connector D (12P).

Fig 4: Checking Continuity Between Terminals Of HandsFreeLink Control Unit 28P Connector And Audio-Navigation Unit Connector D (12P)
Courtesy of AMERICAN HONDA MOTOR CO., INC.

Is there continuity?

YES -Substitute a known-good HandsFreeLink control unit (see CONTROL UNIT INPUT TEST/REPLACEMENT ), and recheck. If the symptom goes away, replace the original HandsFreeLink control unit. If the symptom does not go away, replace the faulty audio-navigation unit (see AUDIO-NAVIGATION UNIT REMOVAL/INSTALLATION ).

NO -There is an open in the wires between the HandsFreeLink control unit and the audio-navigation unit. Replace the affected shielded harness.