Case IH 518438-02 - ACM – ACM: Media track up switch circuit fault

The control module is detecting an electrical anomaly (such as a short, open circuit, or out-of-range resistance) on the circuit dedicated to the media/radio track selection switch located on the armrest.

• MAGNUM AFS Connect
• Magnum 250 AFS Connect
• Magnum 280 AFS Connect
• Magnum 310 AFS Connect
• Magnum 340 AFS Connect
• Magnum 380 AFS Connect
• Magnum 400 AFS Connect
• Steiger AFS Connect
• Quadtrac AFS Connect

1. 1

   Inspect the media track up switch on the armrest for physical damage, sticking, or liquid intrusion (spilled drinks are a common cause).

2. 2

   Disconnect the battery, remove the armrest trim, and inspect the harness connecting the media switch to the ACM for chafed wires, pinched harnesses, or loose connector pins.

3. 3

   Using a multimeter, test the media track up switch for proper operation (check for continuity when pressed and an open circuit or specific baseline resistance when released).

4. 4

   Turn the key to the ON position and check for proper reference voltage coming from the ACM to the switch connector.

5. 5

   Verify if the ACM firmware is up to date via the AFS Pro 1200 display or dealer diagnostic tool, as firmware glitches can trigger false switch faults.

1. 1

   Power Down

   Turn off the tractor, remove the key, and disconnect the negative battery terminal to prevent electrical shorts.

2. 2

   Access the Armrest Internals

   Carefully pry or unscrew the upper trim panels of the Multicontroller armrest to expose the switch clusters and the ACM.

3. 3

   Remove the Faulty Switch

   Disconnect the electrical pigtail from the media track up switch. Depress the retaining tabs on the switch body and push it out of the armrest bezel.

4. 4

   Install the New Switch

   Snap the replacement switch into the armrest bezel and reconnect the electrical connector. Ensure the connector clicks securely into place.

5. 5

   Repair Wiring (If Applicable)

   If the diagnostic checks revealed a damaged wire rather than a faulty switch, splice and heat-shrink the broken wire, or replace the affected armrest sub-harness.

6. 6

   Reassembly

   Reinstall the armrest trim panels and secure all fasteners.

7. 7

   Clear Codes

   Reconnect the battery, power on the tractor, and use the AFS Pro 1200 display or a dealer diagnostic tool to clear the 518438-02 fault code. Test the media track up function to verify the repair.