B145A

B145A-TELEMATICS MIRROR CONTROL CIRCUIT HIGH





For a complete wiring diagram consult Diagrams/Electrical.


- When Monitored:
With the ignition on.

- Set Condition:
The Hands Free Module detects high voltage on the (X793) Microphone Feed circuit.








Diagnostic Test


1. CHECK FOR ACTIVE DTC
With the scan tool, read the active DTC's.
Cycle the ignition switch from off to on at least 5 times, leaving the ignition on for a minimum of 90 seconds per cycle.
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. (X793) MICROPHONE FEED CIRCUIT OPEN
Turn the ignition off.
Disconnect the Hands Free Module C1 harness connector.
Disconnect the Inside Rearview Mirror harness connector.
Measure the resistance of the (X793) Microphone Feed circuit between the HFM C1 connector and the Inside Rearview Mirror connector.
Is the resistance below 5.0 ohms?

Yes


- Go To 3


No


- Repair the (X793) Microphone Feed circuit for an open.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.




3. (X793) MICROPHONE FEED CIRCUIT SHORT TO VOLTAGE
Turn the ignition on.
Measure the voltage of the (X793) Microphone Feed circuit.
Is the voltage above 1.0 volt?

Yes


- Repair the (X793) Microphone Feed circuit for short to voltage.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.


No


- Go To 4




4. INSIDE REARVIEW MIRROR
Replace the Inside Rearview Mirror.
Cycle the ignition switch from off to on at least 5 times, leaving the ignition on for a minimum of 30 seconds per cycle.
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


- Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Hands Free Module.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.


No


- Repair is complete.
- Perform BODY VERIFICATION TEST - VER 1. Body Verification Test.