New Holland NH 4151 – EHR (Electronic Hitch/Hydraulic Remote): Rear Remote No.4 - Manual Operation

This fault code indicates that the electronic controller has detected movement in the spool valve for the 4th rear hydraulic remote that was not commanded by the electronic control lever in the cab. This typically means the valve is being operated via the manual override lever on the valve itself, the manual override mechanism is stuck, or the internal position transducer (potentiometer) inside the valve actuator has failed and is sending an erroneous position signal.

• T6 Series
• T6.140
• T6.180
• T7 Series
• T7.170
• T7.175
• T7.190
• T7.210
• T7.235
• T7.250
• T7.260
• T7.270
• T7.290
• T7.315
• T8 Series
• T8.275
• T8.300
• T8.330
• T8.360
• T8.390
• T8.410
• T8.420
• T8.435
• T9 Series
• T9.390
• T9.450
• T9.505
• T9.600
• T9.615
• T9.670
• T9.700

1. 1

   Visual & Mechanical Inspection: Go to the rear of the tractor and locate the #4 remote valve slice. Check the manual override lever/knob. Ensure it has not been accidentally engaged, left in a continuous flow position, or jammed by debris. It must be able to return freely to the neutral position.

2. 2

   Electrical Connection Check: Inspect the wiring harness and the electrical connector plugging into the #4 EHR valve actuator. Look for pushed pins, corrosion, or wire chafing.

3. 3

   Component Swap Test: To isolate whether the issue is in the valve actuator or the tractor's wiring/controller, swap the electrical connector from the #4 remote valve to an adjacent, known-good remote valve (such as #3 or #5). If the fault code changes to the new valve number (e.g., NH 4137 for Remote No.3), the actuator head on valve #4 is faulty. If the code remains NH 4151, the issue is in the wiring harness or the EHR controller.

4. 4

   Calibration Check: Attempt to perform an EHR valve calibration via the tractor's diagnostic menu (e.g., the HK menu on the Intelliview display) to see if the spool position sensor can be successfully re-zeroed.

1. 1

   Preparation

   Park the tractor on a level surface, lower all implements to the ground, turn off the engine, and cycle the remote levers to relieve all hydraulic pressure in the system.

2. 2

   Clean the Area

   Thoroughly clean the rear remote valve stack to prevent dirt from entering the hydraulic system during disassembly.

3. 3

   Free the Manual Override

   If the manual lever was simply stuck due to rust or dirt, lubricate the linkage and work it back and forth until it springs back to neutral on its own. Clear the code and test.

4. 4

   Replace the Actuator/Valve

   If the manual lever is in neutral but the code persists (and the swap test confirmed a bad valve), the internal position transducer or the electronic driver head has failed.

5. 5

   Removal

   Disconnect the electrical harness from the #4 valve. Depending on the specific valve generation, you may be able to unbolt and replace just the electronic actuator head (powerhead). If it is a sealed unit, you must remove the tie-rods holding the valve stack together and replace the entire #4 valve slice.

6. 6

   Installation

   Install the new actuator head or valve slice. Torque the valve stack tie-rods to the manufacturer's specification to prevent spool binding or leaks.

7. 7

   Calibration

   Turn the key on. Enter the tractor's calibration mode and perform the EHR valve calibration procedure. The controller must learn the new valve's neutral, maximum extend, and maximum retract positions.

8. 8

   Testing

   Clear the fault codes, start the tractor, and verify proper operation of the #4 remote from the cab controls.