DTC Troubleshooting: B1776
DTC B1776:
 Microphone Input/Output Short to Ground/Open
  1. Clear the DTCs with the HDS.
  1. Turn the ignition switch OFF, and then back ON (II).
  1. 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.■
  1. Turn the ignition switch OFF.
  1. Disconnect the 3P connector from the microphone and the 22P connector from the Hands Free Telephone control unit.
  1. Check for continuity between body ground and the No. 9 and No. 10 terminals of the Hands Free Telephone control unit 22P connector individually, then between terminals No. 9 and No. 10.
Is there continuity?
YES -
Repair short in the wires between the Hands Free Telephone control unit and the microphone.■
NO -
Go to Step 8 .
  1. Disconnect the 14P connector from the navigation unit.
  1. Check for continuity between Hands Free Telephone control unit the 22P connector terminal No. 22 and body ground.
Is there continuity?
YES -
Repair short in the wire between the control unit and the navigation unit.■
NO -
Substitute a known-good navigation unit, then recheck. If the symptom goes away, replace the Hands Free Telephone control unit .■