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Home >> Jeep >> 2020 >> Compass Trailhawk >> Repair and Diagnosis >> Engine Performance >> System >> 2.4L - DTCS P104D To P0140 >> DTC Troubleshooting >> P0032-O2 Sensor 1/1 Heater Circuit High >> Diagnostic Test
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Diagnostic Test

  1. CHECK FOR ANY SERVICE BULLETINS OR PCM SOFTWARE UPDATES 
    1. Check for any applicable Service Bulletins or Flash updates related to the DTC.

      Are there any applicable Service Bulletins or Flash updates?

      Yes 

      No 

      • Got to 2
  2. READ AND RECORD DTCS AND ENVIRONMENTAL DATA - ERASE DTCS AND CHECK FOR THE DTC TO RETURN 
    1. With the scan tool, read DTCs in all Electronic Control Units (ECUs) and record on the repair order.
    2. For future reference, with the scan tool, run and save a vehicle Scan Report and all related recorded data.
    3. With the scan tool, erase all DTCs.
    4. Turn the ignition off for a minimum of 10.0 seconds.
    5. Turn the ignition on.
    6. Using the When Monitored and Set Conditions above and recorded data, operate the vehicle in the conditions that set the DTC.
    7. With the scan tool, read DTCs.

      Did the DTC return?

      Yes 

      • Got to 3

      No 

  3. CHECK THE O2 SENSOR (Z909) GROUND CIRCUIT FOR HIGH RESISTANCE BY LOAD TESTING THE CIRCUIT 
    NOTE:

    Read the CIRCUIT LOAD TESTING PROCEDURE for information on building a simple load test tool and for additional load testing information and alternative methods of load testing or voltage drop testing a circuit. Refer to STANDARD PROCEDURE .

    1. Turn the ignition off.
    2. Disconnect the O2 Sensor 1/1 harness connector.
      CAUTION:

      Do not load test any circuits with components still connected to the circuit.

    3. Load test the (Z909) Ground circuit at the O2 Sensor 1/1 harness connector. Note:  refer to the example illustration.
      GC0174957Courtesy of CHRYSLER GROUP, LLC
      NOTE:

      The bulb on the load test tool should be illuminated and bright if there is no resistance in the circuitry. Compare the brightness of the bulb in the load test tool to that of a direct connection across Battery.

      Is the load test bulb illuminated and bright?

      Yes 

      • Got to 4

      No 

      • Repair the (Z909) Ground circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  4. CHECK THE O2 SENSOR 1/1 (K79) HEATER CONTROL CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT 
    1. Disconnect the PCM C2 harness connector.
      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.

    2. Connect the (special tool #10436, Adapter, GPEC Diagnostic).
    3. Check for continuity between the O2 Sensor 1/1 (K79) Heater Control circuit and all other circuits at the GPEC Adaptor.

      Is there continuity between the O2 Sensor 1/1 (K79) Heater Control circuit and any other circuit?

      Yes 

      • Repair the O2 Sensor 1/1 (K79) Heater Control circuit for a short to the circuit that showed continuity.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Got to 5
  5. ISOLATE AND LOAD TEST THE O2 SENSOR 1/1 (K79) HEATER CONTROL CIRCUIT TO CHECK FOR HIGH RESISTANCE 
    CAUTION:

    Do not load test any circuits with components still connected to the circuit.

    1. Connect the (special tool #10436, Adapter, GPEC Diagnostic) to the appropriate PCM connector.
      NOTE:

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

    2. Load test the O2 Sensor 1/1 (K79) Heater Control circuit. Note:  refer to the example illustration.
      GC0174954Courtesy of CHRYSLER GROUP, LLC
      NOTE:

      The bulb on the load test tool should be illuminated and bright if there is no resistance in the circuit. Compare the brightness of the bulb in the load test tool to that of a direct connection across Battery.

      Is the load test bulb illuminated and bright?

      Yes 

      • Got to 6

      No 

      • Repair the O2 Sensor 1/1 (K79) Heater Control circuit for an open or high resistance.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .
  6. CHECK THE O2 SENSOR 1/1 HEATER CONTROL DRIVER FOR PROPER OPERATION 
    1. Turn the ignition off.
    2. Connect the PCM C2 harness connector.
    3. Turn the ignition on.
    4. With the scan tool, actuate the O2 Sensor 1/1 control to the maximum allowable percentage.
    5. Using a 12-volt test light connected to ground, check the O2 Sensor 1/1 (K79) Heater Control circuit at the O2 Sensor 1/1 harness connector.
      NOTE:

      The test light should be illuminated. The brightness will be dependent on the actuation percentage selected.

    6. With the scan tool, actuate the O2 Sensor 1/1 control to the OFF (0%) position.
      NOTE:

      The test light should not be illuminated.

      Does the test light illuminate with the actuator ON and not illuminated with the actuator OFF (0%)?

      Yes 

      No 

      • Got to 7
  7. 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 .
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