Case IH 2112 – Transmission Control Module (TCU) / Drivetrain system: Axle oil pressure switch stuck fault - Axle lube oil

This fault code indicates that the axle lube oil pressure switch has failed to detect adequate pressure within 2 seconds after the machine starts up. Under normal operating conditions, the switch is designed to close when the axle lube oil pressure reaches 0.55 bar (8 psi).

• Steiger T4B
• Case IH STX Steiger Series
• Case IH Steiger Series
• Case IH Quadtrac Series

1. 1

   Visual Inspection: Check that the axle lube oil pressure switch is physically mounted correctly on the axle lube circuit.

2. 2

   Connector Check: Inspect the wiring harness connectors between the pressure switch and the ECU. Ensure the connectors are fully seated, not damaged, the pins are in the correct position, and the fit is tight.

3. 3

   Continuity Test: Test the wiring harness for continuity between the sensor and the ECU to rule out an open circuit or a short to ground.

4. 4

   Mechanical Verification: Ensure the axle actually has adequate fluid levels and that there isn't a genuine low-pressure mechanical failure (which would typically trigger related codes like 2113 - Low oil pressure in the axle, or 2114 - Critical low oil pressure).

1. 1

   Access the Sensor

   Locate the axle lube temperature/pressure switch assembly on the axle lube circuit.

2. 2

   Disconnect

   Unplug the electrical connector from the pressure switch.

3. 3

   Remove

   Unthread the faulty pressure switch from the axle lube port. Have a catch pan ready to collect any residual oil that may weep from the fitting.

4. 4

   Install

   Thread the new OEM pressure switch into the port and tighten to standard specifications.

5. 5

   Reconnect

   Reattach the wiring harness, ensuring the connector clicks securely into place.

6. 6

   Clear Codes & Test

   Turn the key on and use the tractor's diagnostic button (or an Electronic Service Tool) to clear the inactive fault code. Start the machine and verify that the "Trans fault" does not return after the 2-second startup window.