LEMON Manuals: Even more car manuals for everyone
Home >> Jeep >> 2023 >> Grand Cherokee Altitude, AWD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 48 (2.0L - DTCS P0A16 To P1572) >> DTC Troubleshooting >> P1239 Engine Oil Temperature Too Low >> Diagnostic Test

Diagnostic Test

WARNING: This page is about a different variant/trim than selected.
  1. CHECK FOR AN ACTIVE DTC 
    1. Turn the ignition off.
    2. Allow the vehicle to sit with the ignition off in an environment where the temperature will allow the oil temperature to cool down below the engine start model predicted temperature.
    3. Start the engine and allow it to reach normal operating temperature.
    4. With the scan tool, read DTCs and record on the repair order.

      Is the DTC active or pending?

      Yes 

      • Go To  2

      No 

  2. CHECK FOR OTHER DTCS 
    1. Refer to the recorded DTCs.

      Are there any other EOT Sensor DTCs active or pending?

      Yes 

      No 

      • Go To  3
  3. CHECK THE ENGINE OILING AND COOLING SYSTEMS FOR PROPER OPERATION 
    1. The following conditions must be checked:
      • LOW ENGINE OIL
      • ENGINE MECHANICAL TOLERANCES OUT OF SPECIFICATION
      • ENGINE OIL PRESSURE OUT OF SPECIFICATION
      • ENGINE OIL MEETS OEM SPECIFICATION
      • DETERIORATED OR DIRTY OIL
      • ENGINE OIL CONTAMINATED (i.e., coolant and/or fuel)
      • COOLING SYSTEM NOT OPERATING TO SPECIFICATION

      Were any of the above conditions found?

      Yes 

      No 

      • Go To  4
  4. CHECK THE EOT SENSOR CONNECTOR AND TERMINALS 
    1. Turn the ignition off.
    2. Check the EOT Sensor harness connector for proper connection at the EOT Sensor.
    3. Verify that the connector is completely plugged in and properly locked prior to disconnecting.
    4. Disconnect the EOT Sensor harness connector and check for any pushed out, damaged or spread terminals.

      Were any issues found with the connector or terminals?

      Yes 

      • Repair the damaged terminal or properly connect and lock the EOT Sensor harness connector and retest for DTCs.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  5
  5. ISOLATE AND CHECK THE EOT SENSOR (G224) 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 appropriate SYSTEM 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.
    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.

    NOTE:

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

    1. If it is necessary to probe a terminal at a PCM harness connector, connect the special tool # 10436, (GPEC Diagnostic Adapter) to the appropriate PCM harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  6

      No 

  6. 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 appropriate SYSTEM 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.
    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.

    NOTE:

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

    1. If it is necessary to probe a terminal at a PCM harness connector, connect the special tool # 10436, (GPEC Diagnostic Adapter) to the appropriate PCM harness connector.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  7

      No 

  7. CHECK THE ABILITY OF THE PCM TO READ THE EOT SENSOR SIGNAL 
    1. Reconnect the PCM C2 harness connector.
    2. Turn the ignition on.
    3. With the scan tool, read the Engine Oil Temperature Sensor voltage.
      NOTE:

      The sensor voltage should be approximately 5.0 volts (plus or minus 0.1 volts) with the connector disconnected.

    4. Connect a jumper between the (G224) EOT Signal circuit and the Sensor Ground circuit at the EOT Sensor harness connector.
    5. With the scan tool, read the Engine Oil Temperature Sensor voltage.
      NOTE:

      The sensor voltage should be 0.0 volts (plus or minus 0.1 volts) with the jumper in place.

      Does the scan tool display the voltage as described above?

      Yes 

      • Verify that there is good pin to terminal contact in the EOT Sensor and Control Module connectors. Replace the Engine Oil Temperature Sensor if no problems were found with the connectors.
      • Perform the POWERTRAIN VERIFICATION TEST. Refer to POWERTRAIN VERIFICATION TEST .

      No 

      • Go To  8
  8. CHECK RELATED PCM AND COMPONENT CONNECTIONS 
    1. Disconnect all PCM harness connectors.
    2. Disconnect all related in-line harness connections (if equipped).
    3. Disconnect the related component harness connectors.
    4. 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.

    5. Connect all PCM harness connectors. Be certain that all harness connectors are fully seated and the connector locks are fully engaged.
    6. Connect all in-line harness connectors (if equipped). Be certain that all connectors are fully seated and the connector locks are fully engaged.
    7. Connect all related component harness connectors. Be certain that all connectors are fully seated and the connector locks are fully engaged.
    8. With the scan tool, erase DTCs.
    9. Test drive or operate the vehicle in accordance with the when monitored and set conditions.
    10. 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 .
scientia non olet · About LEMON Manuals