Diagnostic Test
WARNING: This page is about a different car, the 2013 RAM 2500 HD and 2012 RAM Pickup. However, it is still accessible from the selected car via links, so may be relevant.
- ACTIVE DTC NOTE:
Diagnose any CAN C Bus Communication DTCs before continuing.
- Turn the ignition one.
- With the scan tool, select View DTCs.
Is the DTC active?
Yes
- Go To 2
No
- Perform the INTERMITTENT DTC diagnostic procedure. Refer to STANDARD PROCEDURE .
- CHECK THE (G31) AAT SIGNAL CIRCUIT FOR A SHORT TO VOLTAGE
- Turn the ignition off.
- Disconnect the Ambient Air Temperature Sensor (AAT) harness connector.
- Turn the ignition on, engine not running.
- Measure the voltage on the (G31) AAT Signal circuit in the AAT Sensor harness connector.
Is the voltage above 5.2 volts?
Yes
- Repair the (G31) AAT Signal circuit for a short to voltage.
- Perform the PCM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Go To 3
- CHECK THE (G31) AAT SIGNAL CIRCUIT FOR AN OPEN/HIGH RESISTANCE
- Turn the ignition off.
- Disconnect the BCM C4 harness connector.
- Measure the resistance of the (G31) AAT Signal circuit between the AAT Sensor harness connector and the BCM C4 harness connector.
Is the resistance below 5.0 Ohms?
Yes
- Go To 4
No
- Repair the (G31) AAT Signal circuit for an open or high resistance.
- Perform the PCM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
- CHECK THE (G931) SENSOR GROUND CIRCUIT FOR AN OPEN/HIGH RESISTANCE
- Measure the resistance of the (G931) Sensor Ground circuit between the AAT Sensor harness connector to the BCM C4 harness connector.
Is the resistance below 5.0 Ohms?
Yes
- Go To 5
No
- Repair the (G931) Sensor Ground circuit for an open or high resistance.
- Perform the PCM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
- Measure the resistance of the (G931) Sensor Ground circuit between the AAT Sensor harness connector to the BCM C4 harness connector.
- CHECK THE AAT SENSOR
- Reconnect the BCM C4 harness connector.
- Turn the ignition on, engine not running.
- Connect a jumper between the (G31) AAT Signal circuit and the (G931) Sensor Ground circuit at the AAT Sensor harness connector.
- With a scan tool, select View DTCs.NOTE:
The scan tool should display the P0072-AMBIENT AIR TEMPERATURE SENSOR CIRCUIT LOW DTC as active or pending with the AAT Sensor harness connector unplugged.
Does the scan tool display the DTC as described above?
Yes
- Verify that there is good pin to terminal contact in the AAT Sensor and Body Control Module (BCM) connectors. If ok, replace the Ambient Air Temperature Sensor.
- Perform the PCM VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Go To 6
- BODY CONTROL MODULE (BCM)
- Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the AAT Sensor and the Body Control Module (BCM).
- Look for any chafed, pierced, pinched or partially broken wires.
- Look for broken, bent, pushed out or corroded terminals. Verify that there is good pin to terminal contact in the AAT Sensor and Body Control Module connectors.
- Perform any Technical Service Bulletins that may apply.
Were there any problems found?
Yes
- Repair as necessary.
- Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .
No
- Replace the Body Control Module (BCM) in accordance with the service information.
- Perform the BODY VERIFICATION TEST. Refer to STANDARD PROCEDURE .