New Holland NH 4150 – EHR (Electro-Hydraulic Remote) Controller / Primary Hydraulic Power System: Rear Remote No.4 - Float position not reached

Triggers when the system commands the #4 rear remote valve to enter the float position, but the internal position sensor (potentiometer) reports that the spool did not physically travel far enough to reach that state. This is typically caused by mechanical binding in the spool, degraded O-rings, a faulty position transducer/potentiometer, or a loss of calibration.

• New Holland T6
• New Holland T7
• New Holland T8
• New Holland T9
• New Holland TG
• New Holland TM
• New Holland Genesis 8670
• New Holland Genesis 8770
• New Holland Genesis 8870
• New Holland Genesis 8970

1. 1

   Attempt to recalibrate the EHR system, as a loss of calibration memory can cause the controller to misinterpret the spool's physical limits

2. 2

   Ensure the hydraulic oil is up to operating temperature (above 5°C); extremely cold oil can cause sluggish spool movement

3. 3

   Use a multimeter or the tractor's diagnostic screen to monitor the voltage sweep of the #4 remote valve potentiometer, looking for dead spots or erratic voltage drops

4. 4

   Inspect the external linkage (if applicable) and the rear of the valve block for debris, corrosion, or physical obstructions preventing full spool travel

1. 1

   Recalibrate the EHR Valve

   Enter the tractor's H-Menu/Calibration mode for the Primary Hydraulic Power System. Select the #4 remote valve. Move the in-cab remote lever fully into the float position. Wait for the lower central display to show 'CAL', indicating the controller has successfully learned the new float position value. Turn the key OFF to store the calibration values. Test the remote. If the code returns, proceed to mechanical repair.

2. 2

   Clean and prepare valve body

   Thoroughly clean the exterior of the #4 remote valve body on the rear of the tractor.

3. 3

   Remove linkage and detent cap

   Remove the linkage/actuator from the front of the spool. Unscrew the large detent cap/pipe from the rear of the remote valve.

4. 4

   Extract and inspect valve spool

   Carefully extract the valve spool from the valve body. Inspect the primary and secondary shuttle valves. Look for blown out or disintegrated O-rings under the detent cap and behind the valve stack, which severely restricts spool travel and hydraulic flow.

5. 5

   Replace O-rings and reassemble

   Replace all missing or flattened O-rings and backup rings. Reassemble the spool, torque the end cap to spec, and perform the EHR calibration again.