LEMON Manuals: Even more car manuals for everyone
Home >> Jeep >> 2023 >> Grand Cherokee Altitude, AWD >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 86 (8P75PH Automatic Transmission - DTCS P2881-00 To U1489-00) >> DTC Troubleshooting >> U0287-00 Lost Communication With Transmission Fluid Pump Module 1 >> Diagnostic Test

Diagnostic Test

WARNING: This page is about a different variant/trim than selected.
  1. CHECK IF TRANSMISSION CONTROL MODULE (TCM) SOFTWARE UPDATE IS AVAILABLE 
    NOTE:

    Read Service Bulletins to determine if the software update is applicable to the customer complaint.

    1. With the scan tool, check if a TCM software update is available that may be related to the customer complaint.

      Is an update available?

      Yes 

      No 

      • Refer to  2.
  2. READ AND RECORD DTCS AND ENVIRONMENTAL DATA - ERASE DTCS AND CHECK FOR DTC TO RETURN 
    1. With the scan tool, read DTCs in all Electronic Control Units (ECU's) and record on the repair order.
    2. With the scan tool, run a vehicle Scan Report, or record the Environmental Data related to the DTCs.
    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 recorded Environmental Data and the When Monitored Conditions above, operate the vehicle in the conditions that set the DTC.
    7. With the scan tool, read DTCs.

    Did the DTC return?

    Yes 

    • Refer to  3.

    No 

  3. CHECK VOLTAGE AT THE INTEGRATED ELECTRIC OIL PUMP (IEP) HARNESS CONNECTOR 
    1. Disconnect the transmission C3 harness connector.
    2. Measure the voltage between the Fused B+ and Ground terminals at the harness connector.

      Is there battery voltage present at the IEP harness connector?

      Yes 

      • Go To  7

      No 

      Go To  4

  4. CHECK THE (A895) FUSED B+ CIRCUIT FUSE 
    1. Inspect Fused B+ circuit for a an open fuse in the Power Distribution Center (PDC).

      Is the Fused B+ circuit fuse open?

      Yes 

      • Repair the (A895) Fused B+ circuit for a short to ground and install new fuse.
      • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

      No 

      Go To  5

  5. CHECK THE (A895) FUSED B+ CIRCUIT FOR HIGH RESISTANCE BY LOAD TESTING THE CIRCUIT 
    1. Disconnect the component harness connector to isolate the (A895) Fused B+ circuit.
    2. Connect the positive lead of the load test tool to the (A895) Fused B+ circuit at the component harness connector (A). Note:  refer to the diagram below.
    3. Connect the negative lead of the load test tool to the ground circuit of the Battery or a good chassis ground.
    4. Ensure that the circuit being tested is being powered on. If the 12.0 volt circuit being tested is an ignition feed for example, the ignition must be on. If testing an output from a relay, verify that the relay is energized and on.
    5. The bulb on the load test tool should be illuminated and bright if there is no resistance in the circuitry.
    NOTE:

    Why load test a circuit?  A load test is used to determine if a circuit is capable of carrying the amperage needed to perform properly. The 3156 bulb in the load tool illustrated, is a simple but effective method of testing circuit functionality. A 3156 Bulb has approximately 6.0 Ohms of resistance when the bulb is powered  and draws approximately 2.0 amps of current. 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: CIRCUIT LOAD TESTING PROCEDURES .

    NOTE:

    A 12-volt test light can be substituted for the load test tool, but only  if the test light draws enough current to effectively load test the circuit. Many high impedance test lights draw very little amperage (less than 0.1 amps) and are not reliable to load test a circuit. To perform a proper load test of a circuit, the tool being used should draw more than approximately 0.75 amps.

    NOTE:

    Why perform a Voltage Drop Test?  To verify with certainty there is not any resistance in the circuit being tested, perform a simple voltage drop test across the 3156 bulb of the load test tool. To do so perform the following:

    1. Connect the leads of a DVOM to the alligator clips on the load test tool while the load test tool is connected in series with the circuit.
    2. Compare the voltage drop across the bulb to the voltage reading across the Battery terminals.
    3. The voltage dropped across the bulb should be equal to the voltage reading across the Battery terminals if there is no resistance in the circuit being tested.

    Example:  2.0 Ohms of resistance in the circuit being tested will cause the voltage measurement across the bulb to be 25% less than when compared to Battery voltage. The reason for this is that the 2.0 Ohms in the circuit makes up 25% of the total circuit resistance of 8.0 Ohms. 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: CIRCUIT LOAD TESTING PROCEDURES .

    GC0174938Courtesy of CHRYSLER GROUP, LLC
    NOTE:

    When probing a circuit at an Electronic Control Unit (ECU) harness connector, always use an appropriate back probing tool to prevent any possible damage to the ECU terminals.

    NOTE:

    Compare the brightness of the bulb in the load test tool to that of a direct connection to Battery.

    Is the load test bulb illuminated and bright?

    Yes 

    • Go To  6

    No 

    • Repair the (A895) Fused B+ circuit for an open or high resistance.
    • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .
  6. CHECK THE (Z910) GROUND CIRCUIT FOR HIGH RESISTANCE BY LOAD TESTING THE CIRCUIT 
    1. Disconnect the component harness connector to isolate the ground circuit.
    2. Connect the positive lead of the load test tool to the positive side of the Battery.
    3. Connect the negative lead of the load test tool to the ground circuit at the component harness connector (A). Note:  refer to the diagram below.
    4. The bulb on the load test tool should be illuminated and bright if there is no resistance in the circuitry.
    NOTE:

    Why load test a circuit?  A load test is used to determine if a circuit is capable of carrying the amperage needed to perform properly. The 3156 bulb in the load tool illustrated, is a simple but effective method of testing circuit functionality. A 3156 Bulb has approximately 6.0 Ohms of resistance when the bulb is powered  and draws approximately 2.0 amps of current. 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: CIRCUIT LOAD TESTING PROCEDURES .

    NOTE:

    A 12-volt test light can be substituted for the load test tool, but only  if the test light draws enough current to effectively load test the circuit. Many high impedance test lights draw very little amperage (less than 0.1 amps) and are not reliable to load test a circuit. To perform a proper load test of a circuit, the tool being used should draw more than approximately 0.75 amps.

    NOTE:

    Why perform a Voltage Drop Test:  To verify with certainty there is not any resistance in the circuit being tested, perform a simple voltage drop test across the 3156 bulb of the load test tool. To do so perform the following:

    • 1. Connect the leads of a DVOM to the alligator clips on the load test tool while the load test tool is connected in series with the circuit.
    • 2. Compare the voltage drop across the bulb to the voltage reading across the Battery terminals.
    • 3. The voltage dropped across the bulb should be equal to the voltage reading across the Battery terminals if there is no resistance in the circuit being tested.

    Example:  2.0 Ohms of resistance in the circuit being tested will cause the voltage measurement across the bulb to be 25% less than when compared to Battery voltage. The reason for this is that the 2.0 Ohms in the circuit makes up 25% of the total circuit resistance of 8.0 Ohms. 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: CIRCUIT LOAD TESTING PROCEDURES .

    GC0174957Courtesy of CHRYSLER GROUP, LLC
    NOTE:

    When probing a circuit at an Electronic Control Unit (ECU) harness connector, always use an appropriate back probing tool to prevent any possible damage to the ECU terminals.

    NOTE:

    Compare the brightness of the bulb in the load test tool to that of a direct connection to Battery.

    Is the load test bulb illuminated and bright?

    Yes 

    • Using the schematics as a guide, check the Transmission C3 Repair any connector and all related in-line connector terminals for corrosion, damage, or pushed out terminals.

    No 

  7. REPLACE THE INTEGRATED ELECTRIC OIL PUMP (IEP) AND RETEST FOR DTCS 
    1. Replace the IEP in accordance with the Service Information.
    2. Connect the IEP 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 

    • Using the schematics as a guide, check the Transmission Control Module (TCM) connector and all related in-line connector terminals for corrosion, damage, or pushed out terminals. Pay particular attention to the power and ground circuits. If no problems are found, replace and program the TCM in accordance with the Service Information. Refer to MODULE, TRANSMISSION CONTROL (TCM), REMOVAL AND INSTALLATION .
    • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

    No 

scientia non olet · About LEMON Manuals