New Holland NH 4173 – EHR (Electro-Hydraulic Remote) Controller: EHR Control No. 2 not calibrated

The control module has lost the stored calibration values (the electrical parameters for the neutral, extend, retract, and float positions) for the #2 Electro-Hydraulic Remote (EHR) control valve or its corresponding armrest lever. Because the system does not know the exact position of the lever or the valve spool, it disables or limits the function of the #2 remote to prevent unintended hydraulic movement.

• T6 Series
• T6000 Series
• T6.120
• T6010
• T6030
• T6070
• T7 Series
• T7000 Series
• T7.220
• T7.235
• T7.250
• T7.270
• T9 Series
• T9.390
• T9.450
• T9.560
• T9.670
• TG Series
• TG245
• TM Series
• TM115
• TM175

1. 1

   Check for accompanying codes (e.g., NH 4174 or NH 4175). If present, resolve these hard electrical failures (open or short circuits) before attempting calibration.

2. 2

   Inspect the #2 SCV control lever/switch in the cab armrest to ensure it moves freely, does not stick, and springs back to the neutral position properly.

3. 3

   Attempt a software calibration procedure before replacing any parts to re-synchronize the lever and the valve.

1. 1

   Prepare tractor

   Park the tractor on a level surface away from obstacles, firmly apply the parking brake, and ensure the ground speed display reads zero.

2. 2

   Disconnect implements

   Disconnect all hydraulic implements from the rear remotes.

3. 3

   Neutralize controls

   Ensure all EHR program switches and levers are in the OFF/Neutral position.

4. 4

   Install diagnostic tool

   Install the diagnostic connector tool into the tractor's diagnostic socket and start the engine.

5. 5

   Navigate to calibration menu

   Using the 'h' (hour), 'm' (minute), and light dimming buttons on the instrument cluster, navigate through the HH menu to H1 and select the hydraulic ram (rear EHR) symbol on the display.

6. 6

   Verify calibration mode

   The lower central display will show 'CAL'.

7. 7

   Select valve

   Select the #2 valve (usually by pulsing the timer switch or following the on-screen prompts to advance to the second valve).

8. 8

   Calibrate lever

   Move the #2 EHR control lever through its full range of motion (extend, retract, float) as prompted by the system to synchronize the lever's potentiometer with the valve spool.

9. 9

   Save calibration

   Once the display indicates the calibration is complete (it will display 'END'), turn the key start switch to the OFF position. This step is critical as it stores the new programming in the module's memory.

10. 10

    Replace defective parts if needed

    If the calibration fails repeatedly or the lever activates on its own, the SCV switch/potentiometer in the armrest is likely defective and must be replaced, followed by a fresh calibration.