DTC B1776: Microphone Input/Output Shorted to Ground
NOTE:
- Check the vehicle 12 volt battery condition first .
- Before you troubleshoot, make sure to follow the General Troubleshooting Information .
- Check the connectors for poor connections or loose terminals.
- 1. Problem verification:
1. Check for HFL DTCs .
Is DTC B1776 indicated?
YES
The failure is duplicated, go to step 2.
NO
Intermittent failure, the system is OK at this time.
- 2. Shorted wire check (MIC+ line):
1. Turn the vehicle to the OFF (LOCK) mode.
2. Disconnect the following connectors.
HandsFreeLink control unit 32P connector HFL microphone 10P connector 3. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode HandsFreeLink control unit 32P connector: disconnected HFL microphone 10P connector: disconnected Test point 1 HandsFreeLink control unit 32P connector No. 2 Test point 2 Body ground Is there continuity?
YES
There is a short to body ground in the wire between the HandsFreeLink control unit and the HFL microphone. Replace the affected shielded harness.
NO
The MIC+ wire is not shorted to ground. Go to step 3.
- 3. Shorted wire check (MIC+ line to another lines):
1. Check for continuity between test points 1 and 2.
Test condition Vehicle OFF (LOCK) mode HandsFreeLink control unit 32P connector: disconnected HFL microphone 10P connector: disconnected Test point 1 HandsFreeLink control unit 32P connector No. 2 Test point 2 HandsFreeLink control unit 32P connector No. 1 Test point 1 HandsFreeLink control unit 32P connector No. 2 Test point 2 HandsFreeLink control unit 32P connector No. 3 Is there continuity?
YES
There is a short in the wires between the HandsFreeLink control unit and the HFL microphone. Replace the affected shielded harness.
NO
The MIC+ wire is OK. Go to step 4.
- 4. HFL microphone check (substitution):
1. Substitute a known-good HFL microphone .
2. Reconnect all the connectors.
3. Check for HFL DTCs .
Is DTC B1776 indicated?
YES
Replace the HandsFreeLink control unit .
NO