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Diagnostic Test

WARNING: This page is about a different car, the 2016 Dodge Journey and 2015 Dodge Journey. However, it is still accessible from the selected car via links, so may be relevant.
  1. DTC IS ACTIVE 
    NOTE:

    Diagnose any CAN - C Communication DTCs before continuing.

    1. Turn the ignition off.
    2. If possible, allow the vehicle to sit with the ignition off for more than 480 minutes in an environment where the temperature is consistent and above - 7° C (19.4° F).
    3. Test drive the vehicle. The vehicle must exceed 48 km/h (30 mph) during the test drive. Do not cycle the ignition off when the test drive is completed.
    4. With a scan tool, select View DTCs.

      Is the status Active or Pending for this DTC?

      Yes 

      • Go To  3

      No 

      • Go To  2
  2. AMBIENT AIR TEMPERATURE 
    1. Turn the ignition off.
    2. Allow the vehicle to sit with the ignition off in an environment where the temperature is consistent and above - 7° C (19.4° F) until the engine coolant temperature is equal to ambient temperature.
    3. Turn the ignition on.
    4. With a scan tool, compare the AAT, ECT, and IAT sensor values.

      Is the Ambient Air Temperature Sensor value within 10° C (18° F) of the other two sensor values?

      Yes 

      No 

      • Go To  3
  3. (G31) AAT SIGNAL CIRCUIT SHORTED TO VOLTAGE 
    Fig 1: Checking AAT Signal Circuit
    GC0099734Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. Disconnect the Ambient Air Temperature Sensor harness connector.
    3. Disconnect the Body Control Module (BCM) D harness connector.
    4. Turn the ignition on.
    5. Measure the voltage of the (G31) AAT Signal circuit in the Ambient Air Temperature Sensor harness connector.

      Is there any voltage present?

      Yes 

      • Repair the (G31) AAT Signal circuit for a short to voltage.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .

      No 

      • Go To  4
  4. (G31) AAT SIGNAL CIRCUIT SHORTED TO GROUND 
    Fig 2: Checking AAT Signal Circuit
    GC0099735Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. Measure the resistance between ground and the (G31) AAT Signal circuit in the Ambient Air Temperature Sensor harness connector.

      Is the resistance above 100 Ohms?

      Yes 

      • Go To  5

      No 

      • Repair the (G31) AAT Signal circuit for a short to ground.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .
  5. (G31) AAT SIGNAL CIRCUIT SHORTED TO THE (G931) AAT SENSOR GROUND CIRCUIT 
    Fig 3: Checking AAT Signal Circuit For A Short To AAT Sensor Ground Circuit
    GC0099736Courtesy of CHRYSLER GROUP, LLC
    1. Measure the resistance between the (G31) AAT Signal circuit and the (G931) AAT Sensor Ground circuit in the Ambient Air Temperature Sensor harness connector.

      Is the resistance above 100 Ohms?

      Yes 

      • Go To  6

      No 

      • Repair the (G31) AAT Signal circuit for a short to the (G931) AAT Sensor Ground circuit.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .
  6. (G31) AAT SIGNAL CIRCUIT OPEN OR HIGH RESISTANCE 
    1. Measure the resistance of the (G31) AAT Signal circuit between the Ambient Air Temperature Sensor harness connector and the BCM D harness connector.

      Is the resistance below 5.0 Ohms?

      Yes 

      • Go To  7

      No 

      • Repair the (G31) AAT Signal circuit for an open circuit or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .
  7. (G931) AAT SENSOR GROUND CIRCUIT OPEN OR HIGH RESISTANCE 
    1. Measure the resistance of the (G931) AAT Sensor Ground circuit between the Ambient Air Temperature Sensor harness connector and the BCM D harness connector.

      Is the resistance below 5.0 Ohms?

      Yes 

      • Go To  8

      No 

      • Repair the (G931) AAT Sensor Ground for an open circuit or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST . .
  8. AMBIENT AIR TEMPERATURE SENSOR 
    Fig 4: Checking Ambient Air Temperature Sensor
    GC0099739Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. Connect the BCM D harness connector.
    3. Connect a jumper wire between the (G931) AAT Sensor Ground circuit and the (G31) AAT Signal circuit in the Ambient Air Temperature Sensor harness connector.
    4. Turn the ignition on.
    5. With the scan tool, read the Ambient Air Temperature Sensor signal voltage.

      Is the voltage below 1.0 volt with the jumper wire in place?

      Yes 

      No 

      • Go To  9
  9. BODY CONTROL MODULE (BCM) 
    1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the Ambient Air Temperature Sensor and the Body Control Module (BCM).
    2. Look for any chafed, pierced, pinched, or partially broken wires.
    3. Look for broken, bent, pushed out or corroded terminals.
    4. Monitor the scan tool data relative to this circuit and wiggle test the wiring and connectors.
    5. Look for the data to change or for the DTC to reset during the wiggle test.
    6. Perform any Technical Service Bulletins that may apply.

      Were any problems found?

      Yes 

      No