Case IH 18328 (4170.02, 4170.03, 4170.04, 518570.07) - ACML – Armrest Control Module (ACM): MFH EHR2 Extend Switch Error State

The control module has detected an electrical fault, such as an open circuit, a short to ground, a short to power, or an out-of-range voltage signal from the MFH EHR2 Extend Switch on the CAN bus network.

• VESTRUM CVX
• Magnum Series (235, 260, 290, 315, 340)
• Steiger Series (350 to 600 horsepower models)
• Puma Series (140, 175, 210)

1. 1

   Inspect the EHR2 extend switch on the Multi-Function Handle for physical damage, sticking, or failure to return to its neutral position

2. 2

   Inspect the wiring harness and CAN bus connections between the Multi-Function Handle and the Armrest Control Module for pinched wires, loose connector pins, or corrosion

3. 3

   Connect diagnostic tool (e.g., 380000843), access the H Menu on the dot matrix display, and view active and stored fault codes in the universal controller

4. 4

   Clear all stored fault codes from the EEPROM using the universal controller menu (HC) and check if code 18328 returns immediately upon actuating the switch

1. 1

   Power Down

   Turn off the tractor, engage the park brake, and disconnect the battery to prevent electrical shorts while working on the armrest.

2. 2

   Access the Armrest

   Remove the protective covers from the armrest console to expose the Armrest Control Module (ACM) and the base of the Multi-Function Handle.

3. 3

   Disconnect the MFH

   Carefully unplug the electrical connectors linking the Multi-Function Handle to the ACM harness.

4. 4

   Replace the Component

   Remove the mounting hardware securing the old handle and install the new Multi-Function Handle / Joystick assembly.

5. 5

   Reassembly

   Reconnect the wiring harnesses securely. Reinstall the armrest console covers.

6. 6

   Calibration and Testing

   Reconnect the battery and turn the key ON. Enter the calibration menu (H1 procedures) to ensure the new handle and its CAN identifiers are recognized by the instrument cluster and ACM. Test the EHR2 extend and retract functions to verify the hydraulic remote operates correctly and the fault code is cleared.