Case IH 2057 – Transmission Control Module (TCU): High range switch open

The control module has detected an open circuit (infinite resistance or lack of voltage return) in the electrical circuit for the transmission's high range switch.

• Maxxum
• Puma
• Steiger
• Farmall

1. 1

   Visual Inspection: Locate the high range switch (typically on the right-hand side of the transmission housing or range synchronizer linkage) and inspect the wiring harness and connector for physical damage, pulled wires, or heavy corrosion.

2. 2

   Harness Continuity Test: Disconnect the switch and use a multimeter to check the wiring harness for continuity back to the transmission controller, specifically testing the transmission control supply circuit and the high range signal circuit.

3. 3

   Switch Resistance/Continuity Test: Test the switch itself with a multimeter by manually actuating it (or shifting the tractor into high range) and checking for continuity. An 'O.L' (open loop) reading while mechanically engaged indicates internal switch failure.

1. 1

   Preparation

   Park the tractor on a level surface, engage the parking brake, turn off the engine, and remove the key.

2. 2

   Access the Switch

   Locate the high range switch on the transmission housing. Clean the area around the switch to prevent dirt from entering the transmission when the switch is removed.

3. 3

   Disconnect

   Unplug the electrical connector from the high range switch.

4. 4

   Removal

   Using the appropriate wrench or socket, unthread/unbolt the faulty high range switch from the transmission housing. (Note: Have a catch pan ready, as a small amount of transmission fluid may weep from the port depending on the switch's location).

5. 5

   Installation

   Thread the new high range switch into the port. Tighten to the torque specification outlined in your specific model's service manual.

6. 6

   Reconnect

   Plug the electrical connector back into the switch. Ensure the locking tab clicks into place.

7. 7

   Calibration/Clearing

   Turn the key on. Use the tractor's diagnostic menu or a CNH Electronic Service Tool (EST) to clear the inactive 2057 fault code.

8. 8

   Test

   Start the tractor and shift through the transmission ranges to verify that high range engages properly and the code does not return.