Case IH 518371-02 - ACM – ACM: Armrest configurable display shortcut switch circuit fault

Erratic, incorrect, or out-of-range signal data coming from the shortcut switch that controls the configurable display, flagging an issue within the armrest's switch circuitry.

• MAGNUM AFS Connect
• Magnum 210
• Magnum 215
• Magnum 230
• Magnum 250
• Magnum 255
• Magnum 260
• Magnum 275
• Magnum 280
• Magnum 285
• Magnum 290
• Magnum 305
• Magnum 315
• Magnum 335
• Magnum 340
• Steiger 280
• Steiger 330
• Steiger 335
• Steiger 380
• Steiger 430
• Steiger 480
• Steiger 500
• Steiger 530
• Puma 175 CVX
• Maxxum
• Optum

1. 1

   Verify CAN Bus Communication: Check the data bus wires (typically yellow and green) at the ACM. They should measure approximately 2.4V to 2.5V.

2. 2

   Check ACM Status: Inspect the ACM circuit board for its status LED. A blinking green LED generally indicates correct communication with the tractor's network.

3. 3

   Inspect Harness and Ground: Check the wiring harness and connectors at the rear of the armrest. Ensure there are no loose pins, corrosion, and that the dedicated ground wire is securely fastened.

4. 4

   Test the Switch: Use a volt/ohm meter to test the configurable display shortcut switch for continuity to confirm if the switch itself has failed internally (shorted or open circuit).

1. 1

   Power down the tractor and disconnect the battery to prevent electrical shorts.

2. 2

   Disassemble the armrest control unit from its mounting position in the tractor cab.

3. 3

   Unplug the main wiring harness on the back of the armrest and remove the ground wire.

4. 4

   Move the entire armrest assembly to a clean workbench.

5. 5

   Disassemble the armrest housing to access the internal switch panel and the ACM board.

6. 6

   Remove the faulty configurable display shortcut switch and install the replacement switch.

7. 7

   Reassemble the armrest housing carefully, ensuring no wires are pinched.

8. 8

   Reinstall the armrest in the tractor, ensuring the ground wire and wiring harness are securely reconnected.

9. 9

   Power on the tractor and verify that the fault code 518371-02 has cleared.

   Note: Some armrest components may require a brief calibration via the display after reassembly.