Case IH U55 – Transmission / EDC (Electronic Draft Control) Controller: PTO Engaged When Calibrating

The Power Take-Off (PTO) was either manually switched on or detected as engaged by the system during a PTO twist sensor or transmission calibration procedure.

• MXM
• Case IH MXM120
• Case IH MXM130
• Case IH MXM140
• Case IH MXM155
• Case IH MXM175
• Case IH MXM190

1. 1

   Verify the PTO switch on the right-hand console is physically in the OFF position before starting the calibration.

2. 2

   Use the tractor's built-in 'H-Menu' diagnostic mode (specifically the H5 menu) to verify if the PTO switch is functioning correctly and sending the proper open/closed signals to the module.

3. 3

   Inspect the wiring harness and connections between the PTO switch and the Transmission/EDC module for shorts to power that might falsely tell the module the PTO is engaged.

1. 1

   Turn OFF the PTO

   Ensure the PTO switch is disengaged.

2. 2

   Repeat Calibration

   Restart the PTO twist sensor or transmission torque calibration procedure from the beginning.

3. 3

   Replace Faulty Switch

   If the U55 code immediately returns despite the switch being physically off, and the H5 diagnostic menu confirms the switch is stuck in the 'closed/engaged' state, remove the right-hand console trim, disconnect the 4-pin harness, and replace the PTO switch.

4. 4

   Final Calibration

   Once the new switch is installed, successfully complete the calibration procedure.