Case IH 2335 – Transmission Controller / Transmission ECU: Pressure indicated on the reverse clutch pressure switch when the clutch solenoids are off.

The transmission controller detects hydraulic pressure at the reverse clutch pressure switch despite the solenoids being deactivated. This condition typically points to a faulty (stuck closed) pressure switch, a short to power in the switch's wiring harness, or a mechanical issue (like a stuck solenoid valve) allowing hydraulic fluid to bypass and pressurize the clutch pack.

• Puma/Mid Range Magnum
• Puma Series
• Magnum Series
• Maxxum / MX / MXM Series
• Steiger Series

1. 1

   Check switch state via the diagnostic menu (H-Menu, Channel 53 or d20). It should read 0 when disengaged and 12000 when engaged.

2. 2

   Disconnect the reverse clutch pressure switch. If the diagnostic reading drops to 0 or the fault clears, the switch is internally shorted/stuck closed.

3. 3

   Test the wiring harness between the switch and the Transmission ECU (e.g., CN3A Pin 17 or CN4 Pin 17) for a short to a +8V/+12V power source.

4. 4

   Inspect the valve block, reverse clutch solenoid, and power shift manifold/shuttle valve assembly for sticking spools or debris allowing fluid to bleed into the circuit.

1. 1

   Secure the tractor

   Park the tractor on a level surface, engage the parking brake, turn off the engine, and securely block the wheels.

2. 2

   Locate the pressure switch

   Locate the reverse clutch pressure switch. Depending on the model, it is typically located on the power shift manifold, the transmission control valve, or the shuttle valve assembly on top of/behind the transmission housing.

3. 3

   Clean the area

   Thoroughly clean the area around the switch to prevent dirt or debris from contaminating the hydraulic system.

4. 4

   Disconnect the wiring harness

   Disconnect the electrical wiring harness from the switch.

5. 5

   Remove the faulty switch

   Unscrew the faulty pressure switch. Have a shop rag or catch pan ready, as a small amount of residual hydraulic fluid will leak out.

6. 6

   Install the new switch

   Thread the new transmission pressure switch into the manifold and tighten it to the OEM torque specification.

7. 7

   Reconnect the wiring harness

   Reconnect the electrical harness.

8. 8

   Test the repair

   Start the tractor, clear the stored fault codes via the diagnostic menu, and test the forward/reverse shuttle operation to ensure the transmission engages smoothly and the code does not return.