Hands Free Module (HFM)

B143F-MICROPHONE 2 CIRCUIT HIGH





For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
With the ignition on.

- Set Condition:
The Hands Free Module (HFM) detects a short to voltage on the (X722) Microphone 2 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.
- Perform the BODY VERIFICATION TEST. Body Verification Test.

2. INSIDE REARVIEW MIRROR
1. Turn the ignition off.
2. Disconnect the Rearview Mirror C2 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. (X722) MICROPHONE CIRCUITS 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 (X722) Microphone circuit.

Is the voltage above 1.0 volt?

Yes

- Repair the (X722) Microphone 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.