Case IH 2756 (518749.02) - DEC – DEC: CAN 1 - EPL status plausibility

The Drivetrain Electronic Controller (DEC) is receiving an implausible status signal from the Electronic Park Lock (EPL) controller over the CAN 1 data bus. The reported state of the electronic park lock does not match the expected state based on other vehicle parameters.

• MAXXUM T4E
• VESTRUM CVX
• Case IH Puma Series
• Case IH Optum Series
• Case IH Magnum Series
• Case IH Maxxum Series

1. 1

   Check Shuttle Lever Position: Ensure the shuttle lever is correctly registering the park position. Check for related codes (like U115) indicating if the shuttle lever is not in the park position or if the lever is damaged.

2. 2

   Inspect Wiring and Connectors: Check the wiring harness between the EPL module and the DEC. Specifically, check pins A4 and C7 on the EPL module for shorts to ground, open circuits, or shorts to supply voltage.

3. 3

   Mechanical Inspection: Verify the mechanical adjustment of the EPL transmission lever and check for excessive wear on the internal braking pads.

4. 4

   Access the 'H' Menu Diagnostics: Use the tractor's diagnostic test switch (special tool 380000843) to enter the 'H' menu mode on the instrument cluster. Navigate to the XA (EPL) sub-menu to view stored calibration values (H2 menu) and check for specific actuator end-stop or timeout errors.

1. 1

   Enter Calibration Mode

   Enter the H1 menu via the ADIC (Advanced Display Instrument Cluster) by selecting the EPL (XA) sub-menu.

2. 2

   Select Calibration Type

   The display will show “CAL”. Use the “h” and “m” buttons on the cluster to switch between the two calibration options: “Inc” for the accelerometer calibration or “SC” for the stroke calibration.

3. 3

   Run Calibration

   Follow the on-screen prompts to complete the stroke and accelerometer calibrations.

4. 4

   Clear EEPROM (If Needed)

   If calibration fails, navigate to the H8 menu to clear the stored calibration information (EEPROM), then re-attempt the H1 calibration.

5. 5

   Test Operation

   Operate the system and check if the error code returns.

6. 6

   Replace Actuator

   If the error code persists or it is impossible to successfully calibrate the EPL, the EPL actuator assembly has failed internally and must be removed and replaced.

7. 7

   Post-Repair Calibration

   After installing a new EPL actuator, you must perform the H1 calibration procedure again before the tractor will operate normally.