Case IH 2540 (123.04) - DEC – UCM (Transmission Control Module / Central Control Unit): Clutch A Pressure Sensor Signal Short to Ground or Open Circuit

The system has detected that the Clutch A Pressure Sensor signal wire is short-circuited to ground or has an open circuit, or that the 5V supply wire to the sensor has an open circuit, preventing the control module from reading the hydraulic pressure applied to Clutch A.

• VESTRUM CVX
• Puma 165
• Puma 170
• Puma 180
• Puma 185
• Puma 195
• Puma 200
• Puma 210
• Puma 215
• Puma 225
• Puma 230
• T7.175
• T7.190
• T7.210
• T7.220
• T7.235
• T7.250
• T7.260
• T7.270
• 7120
• 8120
• 9120
• 7230
• 8230
• 9230

1. 1

   Locate the sensor on the transmission top cover (accessed by removing the cab floor panel) or on the right-hand side of the transmission control manifold.

2. 2

   Inspect the 3-pin connector (X546) for moisture, corrosion, or pushed-out pins.

3. 3

   Test Pin A (BK/WH wire) on the machine-side harness for continuity to sensor ground.

4. 4

   Test Pin B (GN wire) on the machine-side harness for a steady 5V reference supply from the UCM when the key is ON.

5. 5

   Test Pin C (OR wire) on the machine-side harness for continuity back to the UCM, and ensure it is not shorted to the chassis ground.

6. 6

   If the 5V supply and ground are present, and the signal wire has no breaks or shorts, the internal circuitry of the pressure transducer has likely failed.

1. 1

   Preparation

   Park the machine on a level surface, engage the parking brake, turn off the engine, and relieve any residual hydraulic pressure.

2. 2

   Access the Sensor

   Remove the cab floor panel or access panels required to reach the transmission top cover / right-hand hydraulic manifold.

3. 3

   Removal

   Disconnect the X546 electrical connector. Clean the area around the base of the sensor to prevent dirt from entering the hydraulic circuit. Unscrew the faulty Clutch A pressure transducer.

4. 4

   Installation

   Install the new pressure transducer with a new O-ring/seal if not integrated. Torque to the manufacturer's specification.

5. 5

   Reconnection

   Plug in the electrical connector, ensuring the locking tab clicks into place.

6. 6

   Testing

   Turn the key ON and use a diagnostic tool (or the tractor's onboard display) to clear the stored 2540 fault code. Start the tractor and test the transmission for normal operation. A transmission clutch calibration may be required after replacing the pressure sensor to ensure smooth shifting.