Case IH 15328 – Steering Valve Controller: Steering valve spool moved without command

The system detects that the internal spool of the electro-hydraulic steering valve has shifted out of its neutral position without receiving a corresponding input command from the steering wheel or the auto-guidance system.

• Steiger T4B
• Steiger
• Magnum
• Puma
• Maxxum
• Optum

1. 1

   Inspect hydraulic fluid for metal shavings or heavy contamination (leading cause of a sticking steering valve spool)

2. 2

   Inspect the wiring harness and connectors going to the steering valve's spool position sensor (LVDT) for chafed wires, corrosion, or loose pins

3. 3

   Check for accompanying fault codes related to the LVDT sensor or pilot supply pressure issues to isolate electrical from mechanical faults

4. 4

   Perform a manual steering test with the engine running, feeling for binding, hard spots, or delayed response indicating physical scoring inside the valve body

5. 5

   Verify that the primary pilot supply pressure to the steering valve is within OEM specifications

1. 1

   Preparation

   Park the tractor on a level surface, lower all implements, turn off the engine, and actuate the steering wheel to relieve residual hydraulic pressure.

2. 2

   Access and Clean

   Remove the steering column covers or access panels to reach the steering valve (orbital valve). Thoroughly clean the exterior of the valve and surrounding fittings to prevent dirt from entering the hydraulic system during removal.

3. 3

   Disconnect Lines

   Mark all hydraulic hoses (Left, Right, Pressure, Tank, Load Sense) for correct reassembly. Disconnect the hoses and cap the lines immediately.

4. 4

   Disconnect Electronics

   Unplug the electrical connectors for the steering valve controller and LVDT sensors.

5. 5

   Remove Valve

   Remove the mounting bolts securing the steering valve to the steering column/chassis and extract the unit.

6. 6

   Rebuild or Replace

   If replacing: Transfer any necessary fittings to the new steering valve. If rebuilding: Disassemble the valve, inspect the spool and sleeve for scoring, and check the centering springs. Clean all components thoroughly and install a new seal kit.

7. 7

   Installation

   Mount the new/rebuilt steering valve and torque the mounting bolts to spec. Reconnect all hydraulic hoses to their marked positions and plug in the electrical connectors.

8. 8

   Bleed the System

   Start the engine and turn the steering wheel slowly from lock to lock several times to bleed trapped air from the steering cylinders and lines.

9. 9

   Calibration

   Use the Case IH Electronic Service Tool (EST) or the in-cab PLM display to recalibrate the steering system, ensuring the controller learns the new exact neutral position of the spool.