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FCM - Ambient Temp Sensor Input Open

FCM - AMBIENT TEMP SENSOR INPUT OPEN

WHEN MONITORED
Continuous with the ignition on.

SET CONDITION
The FCM detects more than 5.0 volts on the Ambient Temperature Sensor Signal circuit.

POSSIBLE CAUSES
- (G31) Ambient temperature sensor signal circuit short to voltage
- (G930) Ambient temperature sensor ground circuit open
- (G31) Ambient temperature sensor signal circuit open
- Ambient temperature sensor

1. AMBIENT TEMPERATURE SENSOR




Disconnect the Ambient Temperature Sensor harness connector.
Connect a jumper wire between the sensor signal and sensor ground circuits.
Close all vehicle doors.
Turn the ignition on.
With the DRBIII(R) in Sensors, read the Ambient Temperature Sensor voltage.

Q: Is the voltage below 0.5 volt?

YES: Replace the Ambient Temperature Sensor. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Go To 2

2. CHECK THE (G31) AMBIENT TEMPERATURE SENSOR SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE




Turn the ignition off.
Disconnect the IPM C3 harness connector.
Turn the ignition on.
Measure the voltage between the (G31) Ambient Temperature Sensor Signal circuit and ground.

Q: Is there any voltage present?

YES: Repair the (G31) Ambient Temperature Sensor Signal circuit for a short to voltage. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Go To 3

3. CHECK THE (G180) AMBIENT TEMPERATURE SENSOR GROUND CIRCUIT FOR AN OPEN




Turn the ignition off.
Measure the resistance of the (G180) Ambient Temperature Sensor Ground circuit between the IPM C3 harness connector and the Ambient Temperature Sensor harness connector.

Q: Is the resistance above 5.0 ohms?

YES: Repair the (G180) Ambient Temperature Sensor Ground circuit for an open. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Go To 4

4. CHECK THE (G31) AMBIENT TEMPERATURE SENSOR SIGNAL CIRCUIT FOR AN OPEN




Measure the resistance of the (G31) Ambient Temperature Sensor Signal circuit between the IPM C3 harness connector and the Ambient Temperature Sensor harness connector.

Q: Is the resistance above 5.0 ohms?

YES: Repair the (G31) Ambient Temperature Sensor Signal circuit for an open. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test
NO: Replace the Front Control Module. Perform BODY VERIFICATION TEST - VER 1. Body Verification Test