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Home >> Jeep >> 2014 >> Wrangler Sahara, Standard Trans >> Repair and Diagnosis >> External Pages >> Different car >> Section 170 (2.4L - DTCS P000A To P0441) >> DTC Troubleshooting >> P0072-Ambient Air Temperature Sensor Circuit Low >> Diagnostic Test

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.

    NOTE:

    Diagnose and repair any system voltage DTCs before continuing with this test.

    1. Start the engine and allow it to reach normal operating temperature.
      WARNING:

      When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.

    2. With the scan tool, select View DTCs.

      Is the status Active for this DTC?

      Yes 

      • Go To  2

      No 

  2. (G31) AAT SIGNAL CIRCUIT SHORTED TO GROUND 
    Fig 1: Checking AAT Signal Circuit For Short To Ground
    GC0099735Courtesy of CHRYSLER GROUP, LLC
    1. Turn the ignition off.
    2. Disconnect the Ambient Air Temperature Sensor harness connector.
    3. Disconnect the BCM C4 harness connector.
    4. 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  3

      No 

      • Repair the (G31) AAT Signal circuit for a short to ground.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  3. (G31) AAT SIGNAL CIRCUIT SHORTED TO THE (G931) AAT SENSOR GROUND CIRCUIT 
    Fig 2: Checking AAT Signal Circuit For Short To 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  4

      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 .
  4. (G31) AAT SIGNAL CIRCUIT OPEN CIRCUIT OR HIGH RESISTANCE 
    1. Measure the resistance of the (G31) AAT Signal circuit between the Ambient Air Temperature Sensor harness connector and the BCM C4 harness connector.

      Is the resistance below 5.0 Ohms?

      Yes 

      • Go To  5

      No 

      • Repair the (G31) AAT Signal circuit for an open circuit or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  5. AMBIENT AIR TEMPERATURE SENSOR 
    1. Turn the ignition off.
    2. Connect the BCM C4 harness connector.
    3. Turn the ignition on.
    4. With the scan tool, read the Ambient Air Temperature Sensor signal voltage.

      Is the voltage above 4.5 volts with the Ambient Air Temperature Sensor harness disconnected?

      Yes 

      No 

      • Go To  6
  6. 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