Case IH 5507 – UCM (Universal Control Module): Auxiliary Valve Spool Sensor is Open Or Shorted To Ground

The controller is not receiving the expected voltage signal from the sensor that monitors the position of the auxiliary hydraulic valve spool, either because the circuit is broken (open) or the signal wire is grounding out against the chassis.

• skid steer
• Skid Steer Loaders (SSL)
• Compact Track Loaders (CTL)
• Tractors (including Steiger, Puma, and Maxxum series)

1. 1

   Locate the auxiliary valve spool sensor on the hydraulic control valve block. Inspect the sensor connector and the wiring harness leading to it.

2. 2

   Look for broken wires, pulled pins, or a disconnected plug to check for an open circuit.

3. 3

   Inspect the wiring harness for chafing, melted insulation, or pinch points where the bare wire might be touching the machine's metal frame to check for a short to ground.

4. 4

   Use a multimeter to test the signal, ground, and power wires from the sensor connector back to the UCM to verify continuity and ensure there is no continuity to ground on the signal wire.

1. 1

   Secure the Machine

   Lower all hydraulic attachments to the ground, turn off the engine, and relieve hydraulic pressure.

2. 2

   Access the Valve Block

   Remove any necessary access panels to reach the auxiliary hydraulic control valve.

3. 3

   Repair Wiring

   If the diagnostic checks revealed a broken or chafed wire, repair the damaged section of the harness using proper weather-sealed connectors, or replace the harness section. Clear the code and test.

4. 4

   Replace the Sensor

   If the wiring harness tests perfectly fine, the sensor has likely failed internally. Disconnect the electrical connector from the auxiliary valve spool sensor. Unbolt/unscrew the faulty sensor from the auxiliary valve spool. Install the new sensor and torque to OEM specifications. Reconnect the electrical harness.

5. 5

   Clear and Test

   Turn the machine on, clear the UCM fault codes using a diagnostic tool, and operate the auxiliary hydraulics to ensure the code does not return.