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B143F-MICROPHONE 2 CIRCUIT HIGH





For a complete wiring diagram Consult Diagrams/Electrical.

- When Monitored:
With the ignition on.

- Set Condition:
The Hands Free Module detects a fault in any of the microphone circuits.





Diagnostic Test

1. CHECK FOR ACTIVE DTC
With the scan tool, read the active DTC's.
Cycle the ignition switch from off to on.
Attempt to make a phone call with the system.
With the scan tool, read the active DTC's.
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




Turn the ignition off.
Disconnect the Rearview Mirror harness connector.
Turn the ignition on.
With the scan tool, read the active DTC's.
Does the scan tool display this DTC as active?

Yes

- Go to 3

No

- Replace the Rearview Mirror.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.

3. (X722) MICROPHONE IN 2 (+) CIRCUIT SHORTED TO VOLTAGE




Turn the ignition off.
Disconnect the Hands Free Module harness connector.
Turn the ignition on.
Measure the voltage of the (X722) Microphone IN 2 (+) circuit.
Is voltage present?

Yes

- Repair the (X722) Microphone IN 2 (+) circuit for a short to voltage.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Go to 4

4. (X722) MICROPHONE 2 IN (+) CIRCUIT OPEN




Turn the ignition off.
Measure the resistance of the (X722) Microphone 2 IN (+) circuit between the HFM connector and the inside rearview mirror connector.
Is the resistance below 5.0 ohms?

Yes

- Replace the Hands Free Module.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.

No

- Repair the (X722) Microphone 2 IN (+) circuit for an open.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.