Case IH 4121 – EHR (Electronic Hitch/Hydraulic Remote) Controller: Rear Remote No.2 - Spool Deflection Excessive

This code indicates that the internal spool of the #2 rear remote hydraulic valve has traveled beyond its expected or commanded position. This is typically caused by an internal mechanical fault (such as a sticking spool, debris in the valve, or a broken centering spring) or a failure of the valve's electronic position transducer/potentiometer.

• Maxxum
• Steiger T4B
• MAXXUM T4E
• VESTRUM CVX
• Magnum
• Case IH Magnum Series
• Case IH Steiger 4WD Series
• Case IH Puma Series
• Case IH Maxxum Series

1. 1

   Check for Manual Override: Verify that the #2 valve hasn't been manually operated or forced, which can trigger spool position errors.

2. 2

   Attempt Recalibration: Clear the code and attempt to recalibrate the remote valves via the tractor's AFS Pro display monitor.

3. 3

   Inspect Wiring: Check the wiring harness and connector at the #2 rear remote valve for corrosion, pushed pins, or damage that could distort the sensor signal.

4. 4

   Test the Potentiometer: Test the position transducer (potentiometer) on the #2 remote valve for proper resistance and a smooth voltage sweep. A dead spot can make the EHR controller think the spool has over-traveled.

5. 5

   Check for Contamination: Check the tractor's hydraulic system for contamination that could cause the spool to stick mechanically.

1. 1

   Relieve hydraulic pressure

   Park the tractor on a level surface, lower all implements, turn off the engine, and relieve all hydraulic pressure by cycling the remote levers/buttons.

2. 2

   Disconnect electrical harness

   Disconnect the electrical harness from the #2 rear remote valve slice.

3. 3

   Replace potentiometer

   If the diagnostic checks pointed to a faulty position sensor, unbolt and replace the remote valve potentiometer.

4. 4

   Remove remote valve slice

   If the electrical components are functioning correctly, the issue is an internal mechanical fault. You must remove the #2 remote valve slice from the rear valve stack.

5. 5

   Replace or rebuild valve

   Depending on the exact model and dealer recommendations, either install a replacement remote valve slice or rebuild the valve with a new main spool assembly. (Note: Case IH released updated spools with additional bleed holes for certain Magnum models experiencing erratic flow/surging).

6. 6

   Reassemble valve stack

   Reassemble the valve stack, ensuring all O-rings are seated properly and the tie-bolts are torqued to factory specifications.

7. 7

   Reconnect electrical harness

   Reconnect the electrical harness.

8. 8

   Perform calibration

   Power on the tractor and perform the mandatory EHR / Remote Valve Calibration procedure using the cab display or the dealer electronic service tool.