Case IH U106 – Transmission Control Module (TCM): Park lock error during calibration / Park brake not engaged

This code is triggered when the system attempts to run an automatic calibration sequence, but the transmission controller detects that the park brake is either not applied by the operator or the park brake circuit/mechanism is not functioning properly.

• Case IH Puma Series (e.g., Puma 145, 165, 185, 210, 240 CVT)

1. 1

   Ensure operator remains seated during calibration to satisfy the seat switch and that the park brake is physically applied

2. 2

   Verify that the handbrake/park brake switch is registering on the instrument panel

3. 3

   Check the park brake solenoid circuit: with key ON and transmission in neutral, disconnect the solenoid connector and verify approximately 12 volts

4. 4

   Measure resistance to ground at the park brake solenoid connector; there should be continuity (less than 5 ohms). If not, troubleshoot the wiring harness for an open circuit

1. 1

   Clear the Code & Retry

   If the code appeared during a routine calibration, clear the stored calibration information (EEPROM), ensure the park brake is firmly applied, sit in the operator seat to satisfy the seat switch, and restart the calibration.

2. 2

   Inspect the Switch

   If the park brake is physically applied but the system says it is not, access the park brake switch (located at the handbrake assembly). Test the switch for continuity when engaged. If it fails, replace the switch.

3. 3

   Test/Replace the Solenoid

   If the switch is working and the wiring harness has 12V power and good ground, but the park brake still fails to engage mechanically, the park brake solenoid is likely faulty and must be replaced.

4. 4

   Recalibrate

   After replacing the faulty switch or solenoid, re-enter the calibration mode. Note that the engine speed may vary automatically to match the current calibration being processed.