Case IH 18064 – Armrest Control Module (ACM): MFH (multi-function handle) communication error

The control module has lost communication with the Multi-Function Handle over the machine's CAN bus or local interconnect network.

• Magnum
• Steiger T4B
• Magnum series
• Puma series
• Steiger series
• Maxxum series
• Axial-Flow series
• T7 series
• T8 series

1. 1

   Check for related code 18065 ('MFH basic assurance test error'), which confirms a total loss of MFH function.

2. 2

   Remove the armrest covers and inspect the wiring harness between the MFH and the Armrest Control Module (ACM) for chafed wires, pinched harnesses, or loose connections.

3. 3

   Disconnect the MFH and check the connector pins for corrosion, moisture, or pins that have been pushed back into the housing.

4. 4

   Verify that the mechatro/armrest controller is receiving proper voltage and that no related 20A fuses are blown.

5. 5

   Test the CAN bus communication lines for continuity, shorts to ground, or shorts to power.

1. 1

   Power down machine

   Turn off the machine and disconnect the battery to prevent electrical shorts or accidental CAN bus spikes.

2. 2

   Access the handle

   Remove the armrest console covers/trim to access the base of the Multi-Function Handle and the Armrest Control Module.

3. 3

   Disconnect MFH

   Unplug the electrical connector at the base of the MFH.

4. 4

   Remove old joystick

   Remove the mounting hardware securing the MFH to the armrest frame and pull the old joystick out.

5. 5

   Install new MFH

   Seat the new or remanufactured MFH into the armrest and secure it with the mounting hardware.

6. 6

   Reconnect wiring

   Plug in the electrical connector, ensuring the locking tab clicks into place.

7. 7

   Reassemble and power up

   Reinstall the armrest console covers and reconnect the battery.

8. 8

   Calibrate system

   Power on the machine, clear the fault codes, and use the Pro 600/700 display (or dealer service tool) to perform an armrest and SCV (Selective Control Valve) calibration so the ACM recognizes the new handle's parameters.