Case IH 4138 – EHR (Electronic Hitch/Hydraulic Remote) / AUX (Auxiliary): Rear Remote No.3 - Output Stage Faulty

The control module has detected an electrical failure in the output circuit that drives the proportional electro-hydraulic actuator (often called the "pilot head") for the #3 rear remote valve. The controller is unable to send or verify the electrical current required to move the valve spool, which typically results in the #3 remote locking out or failing to reach neutral/float positions.

• Magnum
• Maxxum
• Steiger T4B
• MAXXUM T4E
• Magnum Series
• MX series
• Steiger Series
• Quadtrac
• Maxxum Series
• Puma Series

1. 1

   Perform the 'Swap' Test: Disconnect the electrical harness from the #3 remote valve actuator and swap it with the connector for the #4 remote valve. If the fault code changes to the #4 circuit (e.g., 4142/4143), the actuator/pilot head on valve #3 is internally failed. If the 4138 code persists, the issue is in the tractor's wiring harness or the EHR controller itself.

2. 2

   Inspect the wiring harness between the EHR controller and the rear remote stack for chafing, pinched wires, or corrosion at the connectors, which can cause an open circuit or short-to-ground.

3. 3

   Verify that the armrest control lever/potentiometer for the #3 remote is functioning smoothly.

4. 4

   Attempt to recalibrate the remote valves via the A-post instrument cluster or the H-Menu (usually H1 for calibrations). If the valve fails to calibrate, the actuator is likely dead.

1. 1

   Relieve Pressure

   Turn off the tractor. Cycle the remote levers/switches in the cab and use the manual pressure relief bleeders at the rear couplers to ensure all hydraulic pressure is relieved from the system.

2. 2

   Clean the Area

   Thoroughly clean the #3 rear remote valve block assembly to prevent dirt from entering the hydraulic system during disassembly.

3. 3

   Disconnect Electronics

   Unplug the electrical harness connector from the #3 electro-hydraulic actuator.

4. 4

   Remove the Actuator

   Remove the retaining screws/bolts holding the proportional actuator (pilot head) to the main valve body. Carefully pull the actuator straight off the valve spool.

5. 5

   Inspect the Spool

   Ensure the mechanical valve spool moves freely and is not scored or physically binding. If the spool is seized, the entire valve section must be replaced.

6. 6

   Install New Actuator

   Lubricate the O-rings on the new actuator with clean hydraulic fluid. Slide it over the spool and secure it to the valve body, torquing the bolts to OEM specifications.

7. 7

   Reconnect and Calibrate

   Reconnect the electrical harness. Turn the key on and perform the EHR remote valve calibration procedure (using the tractor's display or the EST diagnostic tool) so the controller can learn the new actuator's neutral and end-of-stroke electrical limits.