Case IH R23 – EHR (Electronic Hydraulic Remote) Control System / XCM (Central Controller) / Armrest Controller: CAN Messages Received By The EHR Valve 2 Are Corrupted Or Missing

This indicates a communication failure on the tractor's Controller Area Network (CAN) bus. Specifically, the central controller is either receiving garbled data or no data at all from the electronic pilot head/module on the #2 Electronic Hydraulic Remote (EHR) valve.

• MXM
• Case IH MXM Series (MXM 120, 130, 140, 155, 175, 190)
• Case IH Maxxum Series (100, 110, 115, 120, 125, 130, 140 Multicontroller)
• Case IH Magnum Series (MX210-MX285, 235-340)
• Case IH Steiger / Quadtrac Series
• Case IH Puma Series

1. 1

   Check for companion codes (e.g., R13 for Valve 1, R33 for Valve 3). If multiple valves are reporting missing CAN messages, the issue is likely a main CAN bus wiring failure or a central controller issue rather than the valve itself.

2. 2

   Inspect the EHR Valve 2 connector at the rear hydraulic block for water ingress, bent pins, pushed-out pins, or corrosion.

3. 3

   Verify the EHR valve module is receiving a stable 12V power supply and has a good ground.

4. 4

   Perform a CAN bus continuity test on the CAN High and CAN Low wires from the EHR Valve 2 connector back to the XCM/Armrest controller.

1. 1

   Disconnect Battery

   Always disconnect the tractor's battery before servicing CAN bus components to prevent voltage spikes.

2. 2

   Repair Wiring

   If the diagnostic checks revealed a short, open circuit, or corroded connector on the CAN lines, repair the wiring harness or splice in a new pigtail connector.

3. 3

   Replace the EHR Pilot Head/Valve

   If the wiring, power, and ground are all intact, the electronic module (pilot head) on EHR Valve 2 has failed internally and must be replaced. Remove the retaining bolts holding the electronic pilot head to the mechanical spool valve and install the new unit.

4. 4

   Perform Calibration

   After replacing an EHR valve or its electronic module, the non-volatile memory must be updated. You must perform a hydraulic calibration procedure (often accessed via the tractor's "H-Menu" on the instrument cluster, specifically the H1 or HA calibration modes for MXM series) so the central controller can learn the new valve's neutral and limit positions.