B1437-VOICE RECOGNITION/PHONE SWITCH INPUT CIRCUIT HIGH
For a complete wiring diagram Refer to Section 8W.
- When Monitored:
With the ignition on.
- Set Condition:
The Hands Free Module detects voltage above 4.7 volts on the (X730) Voice Recognition/Phone Switch Signal circuit.
| Possible Causes |
| (X730) VOICE RECOGNITION/PHONE SWITCH SIGNAL CIRCUIT SHORT TO VOLTAGE |
| (X730) VOICE RECOGNITION/PHONE SWITCH SIGNAL CIRCUIT OPEN |
| (X835) SENSOR GROUND CIRCUIT OPEN |
| INSIDE REAR VIEW MIRROR |
| HANDS FREE MODULE |
Diagnostic Test
1. CHECK FOR ACTIVE DTCWith 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.
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. CHECK THE VOLTAGE OF THE (X730) VOICE RECOGNITION/PHONE SWITCH SIGNAL
Turn the ignition off.
Disconnect the Inside Rear View Mirror C2 harness connector.
Turn the ignition on.
Measure the voltage of the (X730) Voice Recognition/Phone Switch Signal circuit.
Is the voltage above 5.3 volts?
Yes
- Repair the (X730) Voice Recognition/Phone Switch Signal circuit for a short to voltage.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
No
- Go To 3
3. INSIDE REAR VIEW MIRROR
Turn the ignition off.
Connect a jumper wire between (X730) Voice Recognition/Phone Switch Signal circuit and the (X835) Sensor Ground circuit.
Turn the ignition on.
With the scan tool, monitor the VR Phone Switch Voltage.
Is the voltage approximately 0 volts?
Yes
- Replace the Inside Rear View Mirror in accordance with the service information.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
No
- Go To 4
4. (X730) VOICE RECOGNITION/PHONE SWITCH SIGNAL CIRCUIT OPEN
Turn the ignition off.
Disconnect the Hands Free Module harness connector.
Measure the resistance of the (X730) Voice Recognition/Phone Switch Signal circuit between the HFM connector and the inside rear view mirror connector.
Is the resistance below 5.0 ohms?
Yes
- Go To 5
No
- Repair the (X730) Voice Recognition/Phone Switch Signal circuit for an open.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
5. (X835) SENSOR GROUND CIRCUIT OPEN
Measure the resistance of the (X835) Sensor Ground circuit between the HFM connector and the inside rear view mirror connector.
Is the resistance below 5.0 ohms?
Yes
- Inspect the wiring and connectors for damage or shorted circuits. If ok, replace and program the Hands Free Module in accordance with the service information.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).
No
- Repair the (X835) Sensor Ground circuit for an open.
- Perform BODY VERIFICATION TEST – VER 1. (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES - STANDARD PROCEDURE).