Case IH 2549 – UCM (Universal Control Module) / Transmission and Chassis Controller: Brake pressure transducer – short to 12V

The control module is receiving a voltage signal from the right brake pressure transducer that is higher than the expected maximum range. This condition typically points to a short circuit to the power supply within the sensor itself, a short in the wiring harness, or a faulty connector.

• Optum
• Case IH Puma series (e.g., 115, 125, 130, 140, 150, 160, 165, 170, 180, 185, 195, 210, 225, 240, including CVX models)
• Case IH Maxxum series
• Case IH Magnum and Steiger series

1. 1

   Inspect the brake pressure transducer connector (e.g., X-549) and the UCM connector (e.g., X-953). Ensure they are securely connected, undamaged, and pins are tight and in the correct position.

2. 2

   Check for external power interference (e.g., a booster or jump box) which can cause temporary over-voltage codes. Disconnect if present and retest.

3. 3

   Disconnect the transducer connector, turn the ignition ON, and measure voltage at the harness to ensure it is receiving the correct reference voltage and the signal wire is not shorted directly to the 12V power wire.

4. 4

   Trace the wire harness between the transducer and the UCM to check for chafing, melted insulation, or pinched wires.

1. 1

   Turn off the tractor, lower any implements, and engage the parking brake.

2. 2

   Locate the right brake pressure transducer (or the specific transducer indicated if ABS/pneumatic trailer brakes are fitted).

3. 3

   Disconnect the electrical connector at the brake pressure transducer.

4. 4

   Unthread and remove the faulty brake pressure transducer from the brake line.

   Relieve system pressure before removal. Be prepared to catch a small amount of fluid if it is a hydraulic sensor, or drain air tanks if it is a pneumatic sensor.

5. 5

   Install the new brake pressure transducer and tighten to the manufacturer's specified torque.

6. 6

   Reconnect the electrical connector.

7. 7

   Turn the ignition ON. Clear the error code 2549 from the UCM using the instrument cluster menus or a diagnostic service tool.

8. 8

   Test the brake system for normal operation and ensure the fault code does not return.