Case IH 1919-07 - UCM – UCM: Rear pilot head #1 reporting that the spool valve is stuck

The microprocessor inside the remote valve's pilot head has detected low or no movement from the main spool valve. This can occur if the spool physically binds due to contamination, or if the pilot head's internal sensor/solenoid fails, causing it to report the lack of movement over the CAN bus.

• MAGNUM AFS Connect
• Magnum Series 210, 235, 250, 260, 280, 290, 310, 340, 370, 380
• Puma Series 185, 200, 220, 240
• Steiger / Quadtrac Series 350, 400, 420, 450, 470, 500, 580
• Optum Series 270, 300

1. 1

   Clear and Retest: Check if the error code is still active. Clear the code and test the system for normal operation to rule out a temporary glitch.

2. 2

   Check Hydraulic Pressure: Verify that the regulated circuit hydraulic pressures are correct. Incorrect pressure can prevent the spool from moving.

3. 3

   Software and Calibration: Ensure all pilot heads are at the same software level. Download the most current software into all remote valves if necessary. Renumber the remote valves, calibrate the armrest control levers, and run the remote valve calibration procedure.

4. 4

   Manual Spool Test: Remove the pilot head from the affected remote valve. Press on the end of the spool with your thumb to test its operation. The spool should move freely within the bore and extend out slightly.

1. 1

   Clean the Spool (If physically stuck)

   If the manual thumb test reveals the spool is binding, slide the offending spool out of the valve block. Flush the bore and the spool using brake cleaner and compressed air to remove any dirt or metal fragments. Crucial Note: Do NOT use any abrasives (like sandpaper or emery cloth) on either the spool or the spool bore, as this will ruin the tight machining tolerances.

2. 2

   Replace the Pilot Head (If spool moves freely)

   If the spool moves perfectly fine by hand but the code persists, the pilot head itself has failed. The pilot head cannot be serviced internally; it must be replaced as a complete assembly.

3. 3

   Reassign the Valves

   After installing a new pilot head, you must use the tractor's display/diagnostic system to reassign (renumber) the valves so the UCM and ARU recognize the new module.

4. 4

   Preventative Maintenance

   Because contamination is the #1 cause of stuck spools, drain the hydraulic system, replace the hydraulic filters, and ensure the work area is spotless during reassembly.