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Home >> Jeep >> 2024 >> Gladiator Nighthawk, Part Time T/Case Control, Automatic Trans >> Repair and Diagnosis (Single Page) >> Engine Performance >> System >> 3.6L (GPEC 2A) - DTCS P00FD To P0121 >> DTC Troubleshooting >> P0111-Intake Air Temperature Sensor 1 Performance >> Diagnostic Test
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Diagnostic Test

  1. CHECK FOR AN ACTIVE CONDITION 
    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 -64°C (83.2°F) until the engine coolant temperature is equal to, or close to the environmental ambient temperature.
    3. Turn the ignition on.
    4. With a scan tool, compare the AAT, ECT, and IAT Sensor values.

      Is the Intake Air Temperature Sensor value within 15°C (27°F) of the other two sensor values?

      Yes 

      No 

      • Go To  2
  2. ISOLATE AND CHECK THE IAT SENSOR (K21) TEMP SIGNAL CIRCUIT FOR AN OPEN/HIGH RESISTANCE 
    1. The ignition must be off when checking the continuity of a circuit.
    2. Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and the component harness connector containing the circuit being tested. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
    3. Before measuring the resistance of any circuit, first measure the resistance between the two leads of the DVOM. Note:  The meter leads can add resistance to the measurement value.
    4. Connect one lead of the DVOM to the circuit being tested at the component harness connector.
    5. Connect the other lead to the circuit being tested at the GPEC Adaptor and measure the resistance of the circuit.
    6. If it is necessary to probe a terminal at a PCM harness connector, connect the (special tool #10436, Adapter, GPEC Diagnostic) to the appropriate PCM harness connector.
      NOTE:

      The GPEC Diagnostic Adaptor can add up to 1.5 Ohms of resistance to the circuit.

      CAUTION:

      Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the GPEC Diagnostic Adaptor to perform the diagnosis.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  3

      No 

  3. ISOLATE AND CHECK THE (K900) SENSOR GROUND CIRCUIT FOR AN OPEN/HIGH RESISTANCE 
    1. The ignition must be off when checking the continuity of a circuit.
    2. Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and the component harness connector containing the circuit being tested. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
    3. Before measuring the resistance of any circuit, first measure the resistance between the two leads of the DVOM. Note:  The meter leads can add resistance to the measurement value.
    4. Connect one lead of the DVOM to the circuit being tested at the component harness connector.
    5. Connect the other lead to the circuit being tested at the GPEC Adaptor and measure the resistance of the circuit.
    6. If it is necessary to probe a terminal at a PCM harness connector, connect the (special tool #10436, Adapter, GPEC Diagnostic) to the appropriate PCM harness connector.
      NOTE:

      The GPEC Diagnostic Adaptor can add up to 1.5 Ohms of resistance to the circuit.

      CAUTION:

      Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install the GPEC Diagnostic Adaptor to perform the diagnosis.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  4

      No 

  4. CHECK THE ABILITY OF THE PCM TO READ THE INTAKE AIR TEMPERATURE SENSOR SIGNAL 
    1. Connect the PCM C2 harness connector.
    2. Turn the ignition on.
    3. With the scan tool, read DTCs.
      NOTE:

      The P0113-INTAKE AIR TEMPERATURE SENSOR CIRCUIT HIGH DTC should display as active or pending with the Intake Air Temperature harness connector disconnected.

    4. Turn the ignition off.
    5. Connect a jumper between the (K21) IAT Signal circuit and the (K900) Sensor Ground circuit at the Intake Air Temperature Sensor harness connector.
    6. Turn the ignition on.
    7. With the scan tool, read DTCs.
      NOTE:

      The P0112-INTAKE AIR TEMPERATURE SENSOR CIRCUIT LOW DTC should display as active or pending with the jumper in place.

      Do the DTCs display as described above?

      Yes 

      No 

      • Go To  5
  5. CHECK RELATED PCM AND COMPONENT CONNECTIONS 
    1. Perform any Service Bulletins that apply.
    2. Disconnect all PCM harness connectors.
    3. Disconnect all related in-line harness connections (if equipped).
    4. Disconnect the related component harness connectors.
    5. Inspect harness connectors, component connectors, and all male and female terminals for the following conditions:
      • Proper connector installation.
      • Damaged connector locks.
      • Corrosion.
      • Other signs of water intrusion.
      • Weather seal damage (if equipped).
      • Bent terminals.
      • Overheating due to a poor connection (terminal may be discolored due to excessive current draw).
      • Terminals that have been pushed back into the connector cavity.
      • Check for spread terminals and verify proper terminal tension.

      Repair any conditions that are found.

    6. Reconnect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
    7. Reconnect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
    8. Reconnect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
    9. With the scan tool, erase DTCs.
    10. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
    11. With the scan tool, read DTCs.

      Did the DTC return?

      Yes 

      No 

      • The wiring or poor connection problem has been repaired.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .