Case IH 518591-02 - ACM – ACM: Transmission display shortcut switch circuit fault

Indicates an electrical circuit malfunction—such as an open circuit, short circuit, or out-of-range voltage—originating from the specific shortcut button/encoder used to quickly pull up the transmission operating screen on the tractor's display.

• MAGNUM AFS Connect
• Case IH Magnum AFS Connect series (e.g., 250, 280, 310, 340, 400)
• Case IH Steiger / Quadtrac AFS Connect series
• Case IH Optum AFS Connect series

1. 1

   Verify the symptom by pressing the transmission shortcut key on the Multicontroller armrest to see if the AFS Pro 1200 monitor responds. Test other shortcut keys to determine if the issue is isolated to a single switch or the entire keypad.

2. 2

   Inspect the wiring harness connecting the shortcut keypad/encoder to the Armrest Control Module (ACM) for pinched wires, chafing, or disconnected plugs.

3. 3

   Check for other related ACM communication codes (e.g., 1012 'No communication with the ACM') which might indicate a broader module failure rather than a single switch failure.

4. 4

   Use a multimeter to test the resistance and continuity of the transmission shortcut switch circuit to verify if the physical button has failed internally.

1. 1

   Power Down

   Turn off the tractor and disconnect the battery to prevent electrical damage while working on the CAN-bus modules.

2. 2

   Access the ACM / Keypad

   Carefully remove the trim panels on the Multicontroller armrest to expose the shortcut switch cluster and the ACM.

3. 3

   Inspect and Clean Connections

   Disconnect the plug leading to the shortcut switch. Inspect the pins for corrosion, bent terminals, or moisture. Clean with contact cleaner if necessary.

4. 4

   Replace the Component

   If the wiring is intact but the switch fails continuity testing, replace the faulty shortcut switch or the integrated armrest keypad module (depending on whether the switch is serviced separately on your specific trim level).

5. 5

   Reassemble and Calibrate

   Reconnect the harness and reinstall the armrest trim. Reconnect the battery.

6. 6

   Clear Codes

   Turn the key to the ON position. Use the AFS Pro 1200 display or an electronic service tool to clear the pending/active 518591-02 fault code.

7. 7

   Functional Test

   Press the transmission shortcut switch to ensure the transmission control menu successfully populates on the AFS Pro 1200 screen.