Case IH 2259-13 - UCM – UCM: Rear pilot head #8 reporting that spool valve position sensor is not calibrated.

The control module detects that the internal position sensor inside the electronic pilot head for rear remote #8 has lost its calibration values, is reporting out-of-range data, or has suffered an internal controller failure.

• MAGNUM AFS Connect
• Case IH Magnum AFS Connect series
• Case IH Steiger / Quadtrac AFS Connect series
• Case IH Optum series
• Case IH Puma series

1. 1

   Verify Lever/Switch Functionality: Ensure the in-cab remote valve lever or switch for remote #8 is physically returning to the neutral position and isn't sticking.

2. 2

   Attempt Recalibration: Before replacing any parts, attempt to recalibrate the EHR valve. On AFS Connect models, this can often be done through the AFS Pro 1200 display, the armrest/A-post configuration menu, or using the CNH Electronic Service Tool (EST).

3. 3

   Check for Sticking Spool: Ensure the main hydraulic spool isn't physically jammed by debris, which can prevent the sensor from reading the correct neutral position.

4. 4

   Inspect Wiring: Check the electrical connector at the pilot head for remote #8 for damaged pins, corrosion, or broken wires.

1. 1

   Relieve Pressure

   Turn off the tractor and cycle the remote levers/switches to relieve all hydraulic pressure in the system before servicing.

2. 2

   Locate the Valve

   Identify rear remote valve #8 at the rear hydraulic stack. The pilot head is the black electronic actuator block bolted to either end of the mechanical valve slice.

3. 3

   Disconnect Electronics

   Unplug the electrical wiring harness connector from the pilot head.

4. 4

   Remove the Pilot Head

   Remove the socket-head cap screws (usually hex/Allen screws) securing the pilot head to the valve body.

5. 5

   Prep the Surface

   Carefully remove the old pilot head. Ensure the mating surface is clean and that the old O-rings are removed.

6. 6

   Install the New Pilot Head

   Install the new pilot head assembly with new O-rings. Torque the socket-head screws to the specification outlined in your specific model's service manual.

7. 7

   Reconnect and Calibrate

   Reconnect the electrical harness. Crucial Step: A newly installed pilot head must be calibrated before it will function. Use the tractor's display menu (often found in the "HK" or "Armrest" calibration menus) or the EST tool to run the EHR calibration procedure. Note: Some systems may also require you to run a valve re-addressing/renumbering procedure so the UCM recognizes the new pilot head on the CAN bus.