B145A
B145A-TELEMATICS MIRROR CONTROL CIRCUIT HIGHB145A-Telematics Mirror Control Circuit High:
WHEN MONITORED
With the ignition on.
SET CONDITION
The Hands Free Module detects high voltage on the (X793) Microphone Feed circuit.
POSSIBLE CAUSES
- (X793) microphone feed circuit open
- (X793) microphone feed circuit short to voltage
- Inside rear view mirror
- Hands free module
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.
Q: 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 harness connector.
Disconnect the Inside Rear View Mirror C2 harness connector.
Measure the resistance of the (X793) Microphone Feed circuit between the HFM connector and the inside rear view mirror connector.
Q: 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.
Q: 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 REAR VIEW MIRROR
Replace the Inside Rear View Mirror.
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.
Q: 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