Case IH 519042-02 - ACM – ACM: Auto engine brake switch circuit fault

The control module has detected an electrical anomaly—such as an open circuit, a short to ground, or a short to power—in the circuit of the automatic engine brake switch. When this fault is active, the software may disable the automatic engine brake function to prevent erratic operation.

• MAGNUM AFS Connect
• Case IH Magnum AFS Connect Series (Magnum 250, 280, 310, 340, 380, and 400, including Rowtrac variants)
• Case IH Steiger & Quadtrac AFS Connect Series

1. 1

   Visual Inspection: Locate the auto engine brake switch on the Integrated Control Panel (ICP) on the Multicontroller armrest. Inspect the switch for physical damage, sticking, or liquid intrusion (a common issue on armrest panels).

2. 2

   Harness & Connector Check: Access the wiring beneath the armrest panel. Inspect the connector at the switch and the harness routing down to the ACM for pinched wires, chafing, or backed-out pins.

3. 3

   Continuity & Voltage Testing: Test the switch itself for proper continuity when toggled on and off. Check the switch connector for proper reference voltage and a good ground path back to the ACM.

4. 4

   Check for Related Codes: Look for other ACM codes (e.g., low battery voltage or multiple switch faults). If multiple armrest switches are failing simultaneously, the issue is likely a shared ground wire or a failing Integrated Control Panel (ICP) rather than a single switch.

1. 1

   Power Down

   Turn off the tractor and disconnect the negative battery cable to prevent electrical shorts while working on the armrest modules.

2. 2

   Access the ICP

   Carefully pry or unscrew the trim surrounding the Multicontroller armrest to lift the Integrated Control Panel (ICP).

3. 3

   Disconnect the Switch

   Locate the auto engine brake switch connection on the underside of the panel and disconnect the wiring harness.

4. 4

   Replace or Repair

   If the wiring is damaged: Repair the broken wire or replace the affected sub-harness section. If the switch failed the multimeter test: Remove the retaining clips or screws holding the switch in the panel and install the replacement switch. (Note: On some newer AFS Connect models, the ICP is a sealed CAN-bus module, meaning an individual switch cannot be replaced and the entire ICP module must be swapped).

5. 5

   Reassembly

   Reconnect the wiring harness, seat the ICP back into the armrest, and secure the trim.

6. 6

   Clear Codes and Test

   Reconnect the battery. Turn the key to the ON position, use the AFS Pro 1200 display or a diagnostic tool to clear the inactive 519042-02 code, and test the engine brake switch to ensure the fault does not return.