Case IH 518677-02 - ACM – ACM: Hitch Display Shortcut Switch Circuit Fault

Fault code 518677-02 indicates a circuit fault or disconnected state associated with the hitch display shortcut switch (also referred to as the hitch settings selector button). The system interprets the switch as being disconnected or having an open circuit, which prevents the shortcut button from bringing up the hitch configuration menu on the display.

• MAGNUM AFS Connect
• Case IH Magnum AFS Connect series
• Case IH Steiger AFS Connect series

1. 1

   Verify the code is active using the AFS Pro display or the Electronic Service Tool (EST) connected to the CAN1/ISOBUS diagnostic port

2. 2

   Inspect the physical condition of the hitch display shortcut switch on the armrest to see if it is stuck, damaged, or lacks tactile feedback

3. 3

   Inspect the internal armrest harness for pinched wires, chafing, or disconnected plugs

4. 4

   Verify the ACM is receiving proper power and ground (Pin 1 - UNSW B+, Pin 2 - SWB+, and Pin 7 - GND)

5. 5

   Use the EST software to monitor the live status of the armrest switches and observe if the ACM registers any change in state when the shortcut switch is pressed

1. 1

   Preparation

   Park the machine on a level surface, turn off the engine, and turn off the battery disconnect switch to prevent electrical shorts.

2. 2

   Disassemble the Armrest

   Carefully remove the retaining screws and lift the upper cover of the armrest control panel to access the internal switch wiring and the ACM.

3. 3

   Inspect the Switch Connection

   Locate the specific connector for the hitch display shortcut switch (or the integrated keypad it belongs to). Disconnect it and inspect the pins for corrosion, moisture, or pushed-back terminals. Clean with electrical contact cleaner if necessary.

4. 4

   Test/Replace the Switch

   Test the switch for continuity using a multimeter. If the switch is internally failed (open circuit) and is serviced separately, replace the switch. If it is part of an integrated control panel (ICP) or keypad assembly, the entire panel may need to be replaced.

5. 5

   Reassembly

   Reconnect all wiring harnesses securely. Reinstall the armrest cover and tighten all fasteners.

6. 6

   Clear Codes and Test

   Turn the battery disconnect switch back on, turn the key to the ON position, and use the EST or the tractor's display to clear the inactive fault codes. Press the hitch display shortcut switch to verify the hitch menu appears on the screen and the fault code does not return.