Case IH 2540 – UCM (Unit Control Module): A clutch pressure transducer – open circuit or short circuit to ground

The control module has detected a voltage reading from the 'A' clutch pressure transducer that falls outside the normal operating range, specifically pointing to a broken wire (open circuit) or a wire shorting out against the chassis (short to ground).

• Optum
• Puma series (165, 180, 195, 210, 225 CVX)
• Magnum series
• Axial-Flow series (7120, 8120, 9120, 7230, 8230, 9230)

1. 1

   Verify that the tractor battery power supply has not been connected to an external power supply (like a jump box or external charger). If an external power supply is connected, disconnect it and test the system for normal operation, as voltage irregularities can trigger this code.

2. 2

   Inspect the wiring harness and connectors leading to the 'A' clutch pressure transducer for rubbed-through wire insulation (short to ground) or pulled/corroded pins (open circuit).

1. 1

   Locate the Transducer

   Locate the 'A' clutch pressure transducer on the control pressure manifold. On combine schematics, this is often labeled as the CLUTCH TD port on the manifold block.

2. 2

   Test the Circuit

   Use a multimeter to verify continuity between the transducer connector and the UCM harness. Check for continuity to ground on the signal wire to rule out a short.

3. 3

   Replace the Transducer

   If the connector and wiring harness test good, unplug the electrical connector, unthread the faulty transducer from the manifold, and install the replacement part.

4. 4

   Clear and Test

   Once the cause of the error code has been rectified, use the diagnostic interface to clear the error code. Test the system for normal operation by engaging the clutch/PTO to ensure the code does not return.