Case IH 518431-13 - ACM – ACM: Multi-Function Handle (MFH) was disconnected while turned on

A loss of communication, a configuration error, or an internal encoder/sensor disagreement between the Multi-Function Handle (the main joystick) and the tractor's control system.

• MAGNUM AFS Connect
• Magnum 235-340
• Magnum 260
• Magnum 290
• Magnum 315
• Magnum 370
• Magnum 400 AFS Connect
• Steiger Series
• Puma Series

1. 1

   Verify if the armrest was recently disassembled, serviced, or if the MFH connector was bumped/unplugged while the key was in the ON position

2. 2

   Inspect the wiring harness and all connectors between the Multi-Function Handle and the Armrest Control Module (ACM) for damage, unseated connectors, or bent pins

3. 3

   Check for additional ACM codes such as 518431-19 (Incorrect configuration) or 518431-14 (Position sensor disagreement) which indicate a hard failure rather than a simple unplugged connector

4. 4

   Clear the error codes using the Electronic Service Tool (EST) or the Pro 700/1200 display, cycle the key power, and retest the system

1. 1

   Power Down

   Turn the tractor's key switch to the OFF position to prevent further voltage spikes or communication errors.

2. 2

   Access the ACM

   Remove the necessary trim panels on the armrest to access the Armrest Control Module and the base of the Multi-Function Handle.

3. 3

   Reseat Connections

   Disconnect the main harness connector at the base of the MFH. Inspect it for debris or corrosion, clean it with contact cleaner if necessary, and firmly reconnect it to the ACM harness.

4. 4

   Reboot and Calibrate

   Turn the key switch back to the ON position. If the code was triggered simply by a loose connection while powered, reseating it and cycling the power should resolve the 518431-13 code.

5. 5

   Replace the Handle (If Necessary)

   If the wiring is intact but code 518431-14 (sensor disagreement) or 518431-13 remains active and cannot be cleared, the internal position sensors/encoders inside the joystick have failed. The Multi-Function Handle is a sealed unit and must be replaced entirely.

6. 6

   Reconfigure

   If a new handle is installed, use the EST to ensure the ACM recognizes the new component and that no configuration mismatch codes (like 518431-19) are triggered.