LEMON Manuals: Even more car manuals for everyone
Home >> Jeep >> 2020 >> Grand Cherokee Trackhawk >> Repair and Diagnosis >> External Pages >> Different car >> Section 272 (68RFE Automatic Transmission - DTCS P0218-00 To P0871-00 - 2500HD & 3500HD) >> DTC Troubleshooting >> P0714-00-Transmission Temperature Sensor Intermittent >> Diagnostic Test

Diagnostic Test

WARNING: This page is about a different car, the 2019 RAM 3500 HD and 2019 RAM 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK FOR APPLICABLE SERVICE BULLETIN 
    1. Start the engine.
    2. With the scan tool, read and record DTCs and Freeze Frame Data on the repair order.
    3. Check for any Service Bulletins that may apply for this issue.

      Were any Service Bulletins applicable?

      Yes 

      • Perform the applicable Service Bulletin. Erase the DTC and perform the verification test.
      • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

      No, if DTC is stored 

      No, if DTC is active or pending 

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

      Are there any other Transmission Temperature Sensor DTCs active or pending?

      Yes 

      • Perform the applicable diagnostic procedure before continuing with this test procedure. Refer to DIAGNOSTIC CODE INDEX .

      No 

      • Go To  3
  3. WIRE HARNESS INSPECTION 
    1. Turn the ignition off.
    2. Verify that the Transmission Solenoid/TRS Assembly harness connector is fully seated and the primary lock is engaged.
    3. Start the engine and wiggle test the wiring harness and connectors in attempt to duplicate the problem while monitoring the transmission temperature with the scan tool.
    4. Turn the ignition off.
    5. Disconnect the harness connectors at the PCM and Transmission Solenoid/TRS Assembly and inspect for wire chafing or rub conditions, terminals pushed out on the wiring connector, bent terminals at the PCM and Transmission Solenoid/TRS Assembly, water in the connector cavities, presence of corrosion on the terminals of the connectors or components.

      Were any problems found?

      Yes 

      No 

      • Go To  4
  4. CHECK THE (T54) TRANSMISSION TEMPERATURE SIGNAL CIRCUIT FOR PROPER VOLTAGE AT THE TRANSMISSION SOLENOID/TRS ASSEMBLY HARNESS CONNECTOR 
    1. Turn the ignition off.
    2. Disconnect the harness connector at the component of the circuit being tested. Note:  The ECU harness connector should still be connected during this test step.
    3. Turn the ignition on.
    4. Set the DVOM to measure DC voltage.
    5. Connect the negative lead of the DVOM to a known good ground.
    6. With the positive lead of the DVOM, measure the voltage of the circuit being tested at the component harness connector.
    NOTE:

    Normal operating voltage should be between 4.8 and 5.2 volts.

    Does the circuit have the proper voltage present?

    Yes 

    • Go To  5

    No 

    • Go To  6
  5. ISOLATE AND CHECK THE (K900) SENSOR GROUND CIRCUIT FOR AN OPEN/HIGH RESISTANCE 
    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.

    1. Important:  The GPEC Diagnostic Adapter can add up to 1.5 Ohms of resistance to the circuit.
    2. Connect the (special tool #10436, Adapter, GPEC Diagnostic) to the appropriate PCM harness connector.
      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 Diagnostic Adapter and measure the resistance of the circuit.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  8

      No 

  6. ISOLATE AND CHECK THE (T54) TRANSMISSION TEMPERATURE SIGNAL CIRCUIT FOR AN OPEN/HIGH RESISTANCE 
    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.

    1. Important:  The GPEC Diagnostic Adapter can add up to 1.5 Ohms of resistance to the circuit.
      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 Diagnostic Adapter and measure the resistance of the circuit.

      Is the resistance below 3.0 Ohms?

      Yes 

      • Go To  7

      No 

  7. ISOLATE AND CHECK THE (T54) TRANSMISSION TEMPERATURE SIGNAL CIRCUIT FOR A SHORT TO GROUND 
    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.

    1. The ignition must be off when checking a circuit for continuity to ground.
    2. Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and every component harness connector containing the circuit being tested. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
    3. Connect the negative lead of the DVOM to a known good ground.
    4. With the positive lead of the DVOM, probe the circuit being tested at the component harness connector and check for continuity between the circuit and ground.
    NOTE:

    There should be no continuity between ground and the circuit being tested.

    Is there continuity between ground and the circuit being tested?

    Yes 

    • Repair the circuit for a short to ground. Use the wiring diagram as a guide to trace the circuit and look for any in-line connectors to help isolate the location of the short.
    • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

    No 

    • Go To  8
  8. ISOLATE AND CHECK THE (T54) TRANSMISSION TEMPERATURE SIGNAL CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT AT THE PCM 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.

    1. The ignition must be off when performing a resistance check to find a short between circuits.
    2. Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and every component harness connector containing the circuit being tested. At this time leave all in-line connectors connected. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
    3. Connect one lead of the DVOM to the circuit being tested at the GPEC Diagnostic Adapter.
    4. With the other lead of the DVOM probe all other circuits at the GPEC Diagnostic Adapter.
    NOTE:

    With the circuit isolated there should be no continuity between the circuit being tested and any other circuit.

    Is there continuity between the circuit being tested and any other circuit?

    Yes 

    • Repair the short between the circuits that have continuity. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors to help isolate the location of the short.
    • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

    No 

    • Go To  9
  9. ISOLATE AND CHECK THE (K900) SENSOR GROUND CIRCUIT FOR A SHORT TO ANOTHER CIRCUIT AT THE PCM 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.

    1. The ignition must be off when performing a resistance check to find a short between circuits.
    2. Isolate the circuit by disconnecting the Electronic Control Unit (ECU) and every component harness connector containing the circuit being tested. At this time leave all in-line connectors connected. Note:  Use the wiring diagram as a guide to follow the path of the circuit.
    3. Connect one lead of the DVOM to the circuit being tested at the GPEC Diagnostic Adapter.
    4. With the other lead of the DVOM probe all other circuits at the GPEC Diagnostic Adapter.
    NOTE:

    With the circuit isolated there should be no continuity between the circuit being tested and any other circuit.

    Is there continuity between the circuit being tested and any other circuit?

    Yes 

    • Repair the short between the circuits that have continuity. Use the wiring diagram as a guide to trace the circuits and look for any in-line connectors to help isolate the location of the short.
    • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

    No 

    • Go To  10
  10. REPLACE THE TRANSMISSION SOLENOID/TRS ASSEMBLY AND RETEST FOR DTCS 
    1. Replace the Transmission Solenoid/TRS Assembly in accordance with the Service Information. Refer to ASSEMBLY, TRANSMISSION SOLENOID AND TRS, REMOVAL AND INSTALLATION .
    2. Connect the component and Electronic Control Unit (ECU) harness connectors.
    3. Turn the ignition on.
    4. With the scan tool, erase DTCs.
    5. Using the Environmental Data or When Monitored Conditions above, operate the vehicle within the conditions that set the DTC.
    6. With the scan tool, read DTCs.

    Did the DTC return?

    Yes 

    • Go To  11

    No 

  11. CHECK RELATED HARNESS 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 

      NOTE:

      This transmission is equipped with a solenoid for the Torque Converter Clutch (TCC) that is a Variable Force Solenoid (VFS) with close tolerance Pressure/Inductance (PI) curve. If replacing the PCM, it is necessary to transfer the PI data from the old PCM to the new PCM using the scan tool. If the PCM being replaced is non-responsive, the PI data can be retrieved from a 2-D bar code on the exterior of the transmission case. This is done with the scan tool using the "Program Torque Converter Solenoid PI Curve" routine.

      Early build transmissions will have the 2-D barcode label on the right side of the transmission case. Late build transmissions will have the label attached to a machined pad at the top of the case, near the rear of the transmission. The data must be entered into the scan tool in order to upload the information to the PCM. In the event that the exterior BAR code is missing, or it is suspected that the valve body or TCC solenoid has been replaced without uploading the correct PI data into an existing PCM, the transmission oil pan must be removed to retrieve the information from the 2-D bar code on the body of the TCC solenoid.

      No