New Holland NH 4120 – EHR (Electronic Hitch/Hydraulic Remote) controller, Armrest Module (ARU), or Remote Valve Controller: Remote No.2 Spool movement to low

The electronic controller has commanded the #2 rear remote hydraulic valve to open or close, but the internal position sensor (potentiometer) is reporting that the spool has not traveled the expected distance.

• T4
• T6
• T7
• T8
• T9
• T6000
• T7000
• Magnum
• Puma

1. 1

   Check the tractor's hydraulic system pressure to ensure there is adequate pilot pressure to physically move the valve spool.

2. 2

   Inspect the wiring harness and connectors at the #2 rear remote valve for corrosion, moisture, or loose pins.

3. 3

   Use the tractor's diagnostic menu (e.g., the H9 menu) to check the voltage and operation of the armrest potentiometers and the remote valve position sensors.

4. 4

   Swap the electrical connection with an adjacent remote valve (e.g., Remote #1 or #3) to see if the fault follows the valve itself or remains with the #2 circuit (which would point to the armrest control or wiring).

5. 5

   Attempt a remote valve spool travel calibration through the tractor's monitor, as the system may simply have lost its calibration parameters.

1. 1

   Park the tractor on a level surface, turn off the engine, and relieve all hydraulic pressure from the system.

2. 2

   Access the rear remote valve stack at the rear of the tractor.

3. 3

   Disconnect the electrical harness from the #2 remote valve actuator.

4. 4

   If diagnostics point to the armrest control knob failing to send the correct signal, disassemble the armrest console and replace the EHR flow control knob potentiometer.

5. 5

   If the fault is isolated to the valve itself, remove the electronic actuator head/potentiometer from the #2 spool valve. Check the exposed spool for mechanical binding, scoring, or debris.

6. 6

   Clean the spool and valve body. If the spool is mechanically stuck or the internal sensor has failed, replace the remote valve actuator head or the entire valve section.

7. 7

   Reconnect all electrical harnesses and reassemble the valve stack.

8. 8

   Turn on the tractor and enter the calibration menu to perform a 'Valve Spool Calibration' for the rear remotes.

   This step is strictly required anytime a valve, controller, or potentiometer is replaced.