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Home >> Jeep >> 2020 >> Grand Cherokee Trackhawk >> Repair and Diagnosis >> External Pages >> Different car >> Section 273 (68RFE Automatic Transmission - DTCS P0875-00 To U1449-00 - 2500HD & 3500HD) >> DTC Troubleshooting >> P2703-00- Inadequate Element Volume UD >> 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. OTHER DTCS PRESENT 
    1. With the scan tool, check for other transmission DTCs.

      Are there any Pressure Switch Sense circuit DTCs present also?

      Yes 

      No 

      • Go To  2
  2. CHECK UD CLUTCH VOLUME INDEX (CVI) 
    1. With the scan tool, erase Transmission DTCs.
      NOTE:

      The TRANS TEMP DEG must be at least 43° C (110° F) before performing the following steps.

    2. Drive the vehicle and perform at least ten 5-4 kickdowns by depressing the throttle between 40 and 50 TPS degrees at speeds about 1500 to 1700 RPM on the Output Speed sensor.
    3. With the scan tool, read the UD CVI.

      Is the UD CVI below 10?

      Yes 

      • Go To  3

      No 

      • Go To  5
  3. UD CLUTCH CIRCUIT LEAKS IN THE VALVE BODY 
    1. Turn the ignition off.
    2. Remove the transmission oil pan and valve body in accordance with the Service Information.
    3. Check the condition of the UD accumulator springs.
    4. Look for possible leak paths into the UD clutch hydraulics circuit within the valve body.

      Were there any problems found?

      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. It is necessary to update the TCC solenoid PI data in the PCM when replacing the TCC solenoid, Valve Body or Transmission assembly. This is done with the scan tool using the "Program Torque Converter Solenoid PI Curve" routine. The PI data is located on a 2-D BAR code etched on the body of the TCC solenoid. The data must be entered into the scan tool in order to upload the information to the PCM.

      When replacing the TCC solenoid or Valve Body, obtain the PI data before installing the transmission oil pan. When replacing the transmission, the PI data can be obtained from a 2-D bar code on the exterior of the new transmission. 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. If it is suspected that the valve body or TCC VFS has been replaced without uploading the correct PI data into the 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.

      • Repair as necessary.
      • If the Valve Body or the TCC VFS solenoid is replaced, remove the external TCC VFS bar code label from the transmission case.
      • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

      No 

      • Go To  4
  4. AIR CHECK UD CLUTCH CIRCUIT 
    1. Perform an air check on the UD Clutch circuit in accordance with the Service Information.
    2. Watch and listen for UD Clutch piston movement.
    3. Air check all other pump passages for air leakage into the UD Clutch circuit.

      Were any problems found?

      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. It is necessary to update the TCC solenoid PI data in the PCM when replacing the TCC solenoid, Valve Body or Transmission assembly. This is done with the scan tool using the "Program Torque Converter Solenoid PI Curve" routine. The PI data is located on a 2-D BAR code etched on the body of the TCC solenoid. The data must be entered into the scan tool in order to upload the information to the PCM.

      When replacing the TCC solenoid or Valve Body, obtain the PI data before installing the transmission oil pan. When replacing the transmission, the PI data can be obtained from a 2-D bar code on the exterior of the new transmission. 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. If it is suspected that the valve body or TCC VFS has been replaced without uploading the correct PI data into the 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.

      • Repair internal transmission. Pay attention to components related to the UD clutch. Broken or weak return spring or a dislocated snap ring. If no trouble is found in UD clutch component or UD clutch leakage was noted in passage, replace the Pump Assembly.
      • If the Valve Body or the TCC VFS solenoid is replaced, remove the external TCC VFS bar code label from the transmission case.
      • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

      No 

  5. VERIFY PCM OPERATION 
    NOTE:

    The TRANS TEMP DEG must be at least 43° C (110° F) before performing the following steps.

    1. Perform eight learnable starts. A learnable start is defined as follows: Start engine. From a standstill, accelerate lightly to 80 Km/h (50 mph), then brake lightly to a stop. Turn off engine.
    2. With the scan tool, record the CVI for all clutches.
    3. With the scan tool, perform a BATTERY DISCONNECT.
    4. With the scan tool, read the CVIs and compare them to the readings recorded before the BATTERY DISCONNECT.

      Are any of the CVIs less than 5 or different than before the BATTERY DISCONNECT?

      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.

      • Using the schematics as a guide, check the Powertrain Control Module (PCM) terminals for corrosion, damage, or terminal push out. Pay particular attention to all power and ground circuits. If no problems are found, replace the PCM in accordance with the Service Information. Refer to REMOVAL AND INSTALLATION .
      • With the scan tool, perform Quick Learn.
      • Perform the TRANSMISSION VERIFICATION TEST. Refer to TRANSMISSION VERIFICATION TEST .

      No 

      • Test Complete.
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