Hands Free Module (HFM)

B143C-MICROPHONE 1 CIRCUIT HIGH







- When Monitored:
With the ignition on.

- Set Condition:
The Hands Free Module detects a short to voltage on the (X712) Microphone 1 IN (+) circuit.





1. CHECK FOR ACTIVE DTC

NOTE: Verify the connection of the Rearview Mirror harness connector.

1. Turn the ignition on.
2. With the scan tool, read the active DTCs.

Does the scan tool display this DTC as active?

Yes

- Go To 2

No

- If the DTC is stored, check for an intermittent condition. Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, or corroded terminals.

2. INSIDE REARVIEW MIRROR
1. Turn the ignition off.
2. Disconnect the Rearview Mirror harness connector.
3. Turn the ignition on.
4. With the scan tool, read the active DTCs.

Does the scan tool display this DTC as active?

Yes

- Go To 3

No

- Replace the Rearview Mirror.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

3. (X712) MICROPHONE 1 IN (+) CIRCUIT SHORTED TO VOLTAGE




1. Turn the ignition off.
2. Disconnect the Hands Free Module harness connector.
3. Turn the ignition on.
4. Measure the voltage of the (X712) Microphone 1 IN (+) circuit.

Is voltage present?

Yes

- Repair the (X712) Microphone 1 IN (+) circuit for a short to voltage.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

No

- Replace the Hands Free Module.
- Perform the BODY VERIFICATION TEST. Body Verification Test.