Case IH R26 – Central Controller (XCM): EHR Control Unit 2 Full Flow Switch Error

This code indicates an electrical fault, implausible signal, or mechanical failure within the full flow switch circuit of the Electronic Hydraulic Remote (EHR) lever number 2. The controller detects an open circuit, short circuit, or a signal that does not match the lever's physical position, triggering this code and typically disabling the affected remote.

• MXM
• MXM 120
• MXM 130
• MXM 140
• MXM 155
• MXM 175
• MXM 190
• Puma Series
• Magnum Series

1. 1

   Enter the tractor's H-Menu (Diagnostics/Calibration mode) and navigate to the switch test menu (typically H5 on MXM models). Test the EHR 2 lever to see if the controller registers the full flow switch input.

2. 2

   Power off the tractor and inspect the wiring harness between the EHR lever 2 and the Central Controller. Look for pinched wires in the armrest console, corroded pins, or loose connectors.

3. 3

   Disconnect the EHR lever 2 connector. Using a multimeter, test the resistance/continuity of the full flow switch while manually actuating the lever to the full flow detent position.

4. 4

   Check for related codes like R27 (No communication between EHR valve 2 and XCM) or R28 (EHR control unit 2 lever faulty). If multiple codes are present, the issue is highly likely a shared ground or a severed CAN bus harness rather than a single switch.

1. 1

   Preparation

   Park the tractor on a level surface, lower all hydraulic implements to the ground to relieve pressure, turn off the key switch, and disconnect the battery.

2. 2

   Access the Controls

   Remove the retaining screws and panels on the right-hand armrest/side console to expose the EHR lever assemblies.

3. 3

   Harness Repair

   If the diagnostic checks revealed a broken wire in the armrest pivot point (a common failure area), cut out the damaged section and splice in new wire using an approved harness repair kit with heat-shrink connectors.

4. 4

   Component Replacement

   If the switch itself failed the continuity test, disconnect the electrical connector for EHR lever 2. Unbolt the faulty lever assembly from the console bracket and install the replacement unit.

5. 5

   Reassembly

   Reconnect the wiring harness, reinstall the armrest console panels, and reconnect the battery.

6. 6

   Calibration

   Start the tractor and enter the transmission/EDC calibration mode (H-Menu). You must perform the EHR valve calibration procedure so the XCM can learn the potentiometer and switch limits of the new lever. Clear the stored R26 fault code.