Phone Switch Stuck

PHONE SWITCH STUCK





For a complete wiring diagram Consult Diagrams/Electrical

- When Monitored:
With the ignition on.

- Set Condition:
The Hands Free Module detects voltage between 2.8 volts and 3.3 volts on the VR/Phone Switch Signal circuit for more than 30 seconds.





Diagnostic Test

1. CHECKING (X730) VOICE RECOGNITION/PHONE SWITCH SIGNAL CIRCUIT




Turn the ignition off.
Disconnect the Rear View Mirror harness connector.
Turn the ignition on.
Measure the voltage of the (X730) Voice Recognition/Phone Switch Signal circuit in the Rear View Mirror harness connector.
Choose which of the following describes the voltage measured:

Voltage is above 5.3 volts

- Go To2

Voltage is between 4.7 and 5.3 volts

- Go To3

Voltage is below 4.7 volts

- Go To4

2. (X730) VOICE RECOGNITION/PHONE SWITCH SIGNAL CIRCUIT SHORT TO VOLTAGE




Turn the ignition off.
Disconnect the Rear View Mirror harness connector.
Disconnect the Hands Free Module harness connector.
Turn the ignition on.
Measure the voltage of the (X730) Voice Recognition/Phone Switch Signal circuit.
Is the voltage below 1.0 volt?

Yes

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

No

- Repair the (X730) Voice Recognition/Phone Switch Signal circuit for a short to voltage.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.

3. HANDS FREE MODULE




Turn the ignition off.
Disconnect the Rear View Mirror harness connector.
Turn the ignition on.
With the scan tool, read the VR/Phone Switch Signal voltage.
Connect one end of a jumper wire to the VR/Phone Switch Signal circuit at the Rear View Mirror harness connector.
While observing the scan tool, momentarily connect and disconnect the other end of the jumper wire to Sensor Ground at the Rear View Mirror harness connector.

NOTE: The scan tool sensor voltage should switch from above 4.7 volts when jumper is not connected to below 0.6 volts when jumper is connected.

Does sensor voltage switch from above 4.7 volts to below 0.6 volt as described?

Yes

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

No

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

4. (X730) VOICE RECOGNITION/PHONE SWITCH SIGNAL CIRCUIT OPEN




Turn the ignition off.
Disconnect the Rear View Mirror harness connector.
Disconnect the Hands Free Module harness connector.
Measure the resistance of the (X730) Voice Recognition/Phone Switch Signal circuit.
Is the resistance below 10.0 ohms?

Yes

- Go To5

No

- Repair the (X730) Voice Recognition/Phone Switch Signal circuit for an open.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.

5. (X835) SENSOR GROUND CIRCUIT OPEN




Turn the ignition off.
Disconnect the Rear View Mirror harness connector.
Disconnect the Hands Free Module harness connector.
Measure the resistance of the (X835) Sensor Ground circuit.
Is the resistance below 10.0 ohms?

Yes

- Go To6

No

- Repair the (X835) Sensor Ground circuit for an open.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.

6. (X730) VOICE RECOGNITION/PHONE SWITCH SIGNAL CIRCUIT SHORT TO GROUND




Turn the ignition off.
Disconnect the Rear View Mirror harness connector.
Disconnect the Hands Free Module harness connector.
Measure the resistance between ground and the (X730) Voice Recognition/Phone Switch Signal circuit.
Is the resistance above 1000.0 ohms?

Yes

- Go To7

No

- Repair the (X730) Voice Recognition/Phone Switch Signal circuit for a short to ground.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.

7. (X730) VOICE RECOGNITION/PHONE SWITCH SIGNAL CIRCUIT SHORT TO (X835) SENSOR GROUND




Turn the ignition off.
Disconnect the Rear View Mirror harness connector.
Disconnect the Hands Free Module harness connector.
Measure the resistance between (X835) Sensor Ground and the (X730) Voice Recognition/Phone Switch Signal circuit at the Rear View Mirror harness connector.
Is the resistance above 1000.0 ohms?

Yes

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

No

- Repair the (X730) Voice Recognition/Phone Switch Signal circuit for a short to the Sensor Ground circuit.
- Perform the BODY VERIFICATION TEST - VER 1. Body Verification Test.