New Holland NH 4155 – EHR (Electro-Hydraulic Remote) Control Module: Remote No.4 Spool not in neutral at key on

When the tractor's ignition key is turned on, the system detects that the internal spool for the #4 rear remote hydraulic valve is not resting in its centered (neutral) position. This is a safety mechanism designed to prevent unintended hydraulic movement or implement actuation upon startup.

• T6
• T7
• T8
• T9
• T7.220
• T7.270
• T9.390
• TM175
• TM190
• TS100A
• TS115A
• TS135A
• Magnum
• Maxxum
• Puma
• Steiger

1. 1

   Ensure the in-cab control lever, paddle, or joystick for Remote #4 is physically returning to the center/neutral position and is not stuck or obstructed by debris.

2. 2

   Cycle the ignition key off and back on while ensuring the controls are untouched to see if the code clears.

3. 3

   Inspect the wiring harness and electrical connectors running from the EHR controller to the rear remote valve #4 for corrosion, moisture, open circuits, or shorts.

4. 4

   Check the spool position sensor/potentiometer on the remote valve slice for faults (often associated with related codes like 4153 - potentiometer faulty).

5. 5

   Check the valve spool itself for mechanical binding caused by contaminated hydraulic fluid or internal wear.

1. 1

   Secure the Machine

   Park the tractor on a level surface, lower all implements, and relieve hydraulic pressure.

2. 2

   Inspect and Clean

   Locate the rear remote valve stack. Clean the area around Valve #4 to prevent dirt from entering the hydraulic system.

3. 3

   Test Electrical Inputs

   Disconnect the electrical connector at the #4 EHR valve. Use a multimeter to verify that the valve is receiving the correct voltage and ground from the EHR controller when the key is on.

4. 4

   Replace Faulty Components

   If the wiring is intact but the spool position sensor is failing to read neutral, the sensor, the in-cab switch, or the entire EHR valve slice may need to be replaced (depending on whether the sensor is serviceable separately on your specific valve block).

5. 5

   Reassemble and Calibrate

   Once the new switch or valve is installed, you must recalibrate the EHR system. Connect a CDU (Calibration and Diagnostics Unit) or the tractor's onboard diagnostic menu to clear the stored HF (Hydraulic/EHR) memory codes and run the EHR valve calibration routine so the controller learns the new neutral set point.