Case IH 5513 – UCM (Universal Control Module): Implausible Auxiliary Sensor State Vs Auxiliary Command - Stuck Spool Or PRV

This fault indicates a mismatch between the commanded state of the auxiliary hydraulic system and the actual physical position of the auxiliary valve spool. When the controller sends a signal to the Proportional Reducing Valve (PRV) or auxiliary solenoids to move the spool, the spool position sensor monitors the movement. If the sensor reads that the spool has not moved to the commanded position, or has moved when not commanded, this code is triggered.

• skid steer
• Skid Steer Loaders (SSL)
• Compact Track Loaders (CTL)
• SR130
• SR175
• SV185
• SR220
• TR270
• TR320
• TV380

1. 1

   Inspect the wiring harness and connectors leading to the auxiliary valve spool position sensor and the auxiliary solenoids (PRVs) for chafed wires, loose connections, or corrosion.

2. 2

   Test the spool position sensor using a multimeter or diagnostic service tool to monitor voltage output while commanding the auxiliary hydraulics (voltage should change smoothly).

3. 3

   Test the PRV / solenoids by checking their resistance and ensuring they receive the correct voltage from the UCM when commanded.

4. 4

   Check for mechanical binding of the spool due to contaminated hydraulic fluid, metal debris, or scored valve bores if electrical circuits test fine.

1. 1

   Safety First

   Lower the loader arms to the ground, turn off the engine, and cycle the hydraulic controls to relieve all residual hydraulic pressure in the system. Disconnect the negative battery cable.

2. 2

   Locate the Auxiliary Valve Block

   Access the main hydraulic control valve assembly (usually located under the cab, which may need to be tilted forward for access).

3. 3

   Remove and Inspect the Sensor

   Locate the spool position sensor mounted on the auxiliary section of the control valve. Remove it and inspect the tip for physical damage. Replace it if it failed the electrical diagnostic test.

4. 4

   Inspect the PRV / Solenoids

   Remove the proportional reducing valves (solenoids) controlling the auxiliary spool. Inspect the O-rings and the cartridge for debris. Clean with solvent and blow dry. If the solenoid is burnt out or mechanically stuck, replace it.

5. 5

   Inspect the Valve Spool

   If the sensor and solenoids are good, carefully remove the auxiliary valve spool from the valve block. Inspect the spool and the bore for scoring, burrs, or metal shavings.

6. 6

   Clean or Replace

   If the spool is lightly bound by debris, clean the spool and bore thoroughly with hydraulic solvent. If the spool or bore is heavily scored, the spool (or the entire valve section) must be replaced.

7. 7

   Reassembly

   Lubricate the spool, O-rings, and PRV with clean hydraulic fluid before reinstallation. Reconnect all electrical harnesses.

8. 8

   Calibration and Testing

   Reconnect the battery. You may need to use the OEM service tool to clear the UCM fault codes and restore self-learning parameters. Run the machine and test the auxiliary hydraulics to ensure smooth operation without throwing the 5513 code.