New Holland EHR 4138 – EHR (Electronic Hitch/Hydraulic Remote) Controller: Rear Remote No.3 - Output Stage Faulty

An electrical failure within the output stage (the internal driver circuit) of the electro-hydraulic remote (EHR) valve for the third rear hydraulic circuit. The controller has detected that the valve's internal solenoid driver is either experiencing a supply undervoltage/overvoltage, a short circuit, or an internal hardware failure preventing it from actuating the spool correctly.

• T8 Series
• T8.275
• T8.320
• T8.410
• T9 Series
• T7 Series
• MXM Series
• TM Series

1. 1

   Perform a swap test: Disconnect the electrical harness from Rear Remote No. 3 and swap it with an adjacent remote (e.g., Remote No. 2 or No. 4). If the fault code changes to the new remote number, the issue is internal to the valve. If the fault stays as EHR 4138, the issue is in the tractor's wiring harness or the EHR controller.

2. 2

   Check CAN bus resistance: Using a multimeter, check the resistance of the CAN wiring between terminals 2 and 3 (Green and Yellow wires) at the valve connector. The resistance should be approximately 120 ohms.

3. 3

   Check voltage supply: Verify that the valve is receiving proper operating voltage (12V) and has a clean ground. Supply undervoltage or overvoltage can trigger output stage faults.

4. 4

   Perform a hydraulic pressure test: Test the maximum system pressure at the remote valve coupler to ensure it reaches the specified 200–207 bar (2900–3000 psi) to rule out mechanical flow issues.

1. 1

   Depressurize the System

   Turn off the tractor engine, turn the key to the ON position (engine off), and actuate the remote levers to relieve all hydraulic pressure in the rear circuits.

2. 2

   Disconnect Wiring

   Unplug the electrical connector from Rear Remote Valve No. 3. Inspect the pins for corrosion or bent terminals.

3. 3

   Remove the Valve

   Unbolt the tie-rods or mounting bolts holding the remote valve stack together. Carefully remove Rear Remote Valve No. 3, ensuring no dirt or debris enters the hydraulic system.

4. 4

   Install the New Valve

   Install the replacement EHR valve (or the electronic actuator head, if available separately for your specific model year) using new O-rings between the valve slices.

5. 5

   Torque and Reconnect

   Torque the stack bolts to OEM specifications and reconnect the electrical harness.

6. 6

   Calibration/Reprogramming

   The new EHR valve must be calibrated to the tractor. Start the tractor and use the diagnostic menu (e.g., H-menu Mode HL on legacy models, or the IntelliView monitor / diagnostic tool on newer models) to program the remote valve. The system will learn the spool travel limits and neutral positions.