DTC Troubleshooting: B1775 - Without NAV. and Sunroof
  1. Check for continuity between Hands Free Telephone control unit 28P connector terminal No. 13 and HFT microphone 10P connector terminal No. 6.
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.■
NO -
Replace the faulty harness between the Hands Free Telephone control unit and the HFT microphone.■