Case IH 2114 – Transmission Control Unit (TCU): Axle oil pressure low critical fault - Axle lube oil circuit

The axle lube oil pressure switch has failed to detect adequate pressure after the machine has started up. The system expects the switch to close once the axle lube oil pressure reaches the minimum threshold of 0.55 bar (8 psi). If the switch remains open, the system triggers this critical fault to prevent mechanical damage to the axle components.

• Steiger T4B
• STX Series
• Steiger Series
• STX380
• STX430
• STX500
• Steiger 330
• Steiger 535

1. 1

   Check fluid levels and filters: Verify the axle lube oil level is correct and check the axle lube oil filter for any restrictions or clogs.

2. 2

   Inspect wiring and connectors: Ensure the electrical connectors at the pressure switch and the ECU are securely connected, not damaged, and that the pins are tight and in the correct position.

3. 3

   Test circuit continuity: Disconnect the harness and test for continuity between the pressure switch connector and the ECU. Check for any open circuits, breaks, or shorts in the wiring harness.

4. 4

   Verify mechanical pressure: Use a mechanical pressure gauge to test the actual pressure of the axle lube circuit after startup. If the mechanical pressure is below 0.55 bar (8 psi), suspect a mechanical issue (e.g., failing lube pump, severe leak, or blockage). If the mechanical pressure is above 0.55 bar (8 psi) but the fault persists, the pressure switch has failed and is stuck open.

1. 1

   Safely park the tractor on level ground, turn off the engine, and allow the system to depressurize.

2. 2

   Locate the axle lube pressure switch on the axle lube circuit/front frame harness area.

3. 3

   Disconnect the electrical harness connector from the switch.

4. 4

   Unthread and remove the faulty pressure switch.

   Have a catch pan ready for any residual oil.

5. 5

   Lubricate the new O-ring and install it onto the new pressure switch.

6. 6

   Thread the new pressure switch (M18 x 1.5) into the port and tighten it securely.

7. 7

   Reconnect the electrical harness to the new switch.

8. 8

   Start the machine and observe the system to ensure there are no oil leaks.

9. 9

   Use the Electronic Service Tool (EST) or the in-cab display to clear the inactive 2114 fault code and return the machine to normal operation.