Case IH 4556 – EHR (Electronic Hitch/Hydraulic Remote) control module or UCM (User Control Module) / Armrest controller: EHR control no.1 not calibrated

Electronic Hitch/Hydraulic Remote (EHR) control valve number 1 has lost its spool travel calibration data, or a calibration was never successfully completed.

• VESTRUM CVX
• Case IH Magnum
• Case IH Maxxum
• Case IH Puma
• Case IH Steiger

1. 1

   Check the physical lever: Ensure the EHR control lever/switch for Remote No. 1 in the cab armrest physically returns to the dead-center neutral position without sticking.

2. 2

   Check for related electrical codes: Look for codes 4171 (EHR Control No.1 open circuit), 4172 (EHR Control No.1 short circuit), or 4184 (EHR Joystick potentiometer open circuit). If these are present, you have a wiring or sensor failure, not just a calibration issue.

3. 3

   Check the manual override: Verify that the manual override lever on the valve body itself has not been activated, as this disables electronic control and can trigger EHR faults.

4. 4

   Harness inspection: Test the harness continuity from the armrest controls to the controller, and from the controller to the rear remote valves.

1. 1

   Prepare tractor

   Park the tractor safely, engage the parking brake, and ensure the hydraulic oil is warmed up to normal operating temperature.

2. 2

   Enter calibration mode

   Enter the tractor's calibration mode. On many Case IH models, this is done by holding the "PROG" key on the A-post display while turning the ignition key to the ON position (or navigating through the AFS Pro 700/1200 monitor's calibration menus).

3. 3

   Navigate to calibration menu

   Navigate to the EHR / Remote Valve calibration menu (often found under the "ARM" section or "HH menu -> H1" for remote valves).

4. 4

   Calibrate spool travel

   Follow the on-screen prompts to calibrate the spool travel. This typically requires you to pull the EHR lever for Remote No. 1 fully backward into the raise/retract detent, push it fully forward into the lower/extend detent, and then allow it to spring back to the neutral position.

5. 5

   Save calibration

   Turn off the ignition key and wait for at least 30 seconds before restarting the tractor. This allows the controller to save the new calibration values to its memory.

6. 6

   Replace faulty components if needed

   If the calibration fails to save or the code returns immediately, the potentiometer inside the armrest lever or the spool valve itself is likely faulty and requires replacement.