DTC Troubleshooting: B1776 - Without NAV. and Sunroof
  1. Check for continuity between the terminals shown of the Hands Free Telephone control unit 28P connector and the HFT microphone 10P connector.
Is there continuity?
YES -
Substitute a known-good Hands Free Telephone control unit, then recheck. If the symptom goes away, replace the original Hands Free Telephone control unit. If the symptom does not go away, replace the faulty HFT microphone.■
NO -
Replace the faulty harness between the Hands Free Telephone control unit and the HFT/navigation microphone.■