Case IH 518725-02 - ACM – ACM: Rear hitch raise rate switch circuit fault

The system has detected an electrical circuit failure (such as an open circuit, short to ground, or short to power) in the switch responsible for controlling the raise rate (speed) of the rear 3-point hitch.

• MAGNUM AFS Connect
• Case IH Magnum AFS Connect Series 180
• Case IH Magnum AFS Connect Series 200
• Case IH Magnum AFS Connect Series 220
• Case IH Magnum AFS Connect Series 240
• Case IH Magnum AFS Connect Series 250
• Case IH Magnum AFS Connect Series 280
• Case IH Magnum AFS Connect Series 310
• Case IH Magnum AFS Connect Series 340
• Case IH Magnum AFS Connect Series 380
• Case IH Magnum AFS Connect Series 400
• Case IH Steiger AFS Connect Series

1. 1

   Check for Accompanying Codes: Use the Electronic Service Tool to check for other ACM error codes. Make a note of them, clear the codes, and test the system for normal operation to see if the fault returns.

2. 2

   Cycle the Switch: Cycle the rear hitch raise rate switch ON and OFF. If the code clears, it may have been a temporary glitch; if it persists, proceed with hardware diagnostics.

3. 3

   Inspect Connectors: Check all connectors at the Armrest Control Module (ACM) and the Tractor Control Unit (TCU). Ensure the connectors are fully seated, not damaged, and that the pins are in the correct position with a tight fit.

4. 4

   Voltage/Continuity Testing: Test the wiring harness between the raise rate switch and the ACM. Look for an open circuit, a short to ground, or a 5-volt reference that is out of limits (above the upper limit or below the lower limit), which commonly triggers hitch control circuit faults.

1. 1

   Power Down

   Turn off the tractor and disconnect the battery to prevent electrical damage while servicing the armrest console.

2. 2

   Access the ACM

   Remove the armrest console covers to access the Armrest Control Module and the integrated rear electronic draft controls.

3. 3

   Harness Inspection

   Visually inspect the wiring harness connecting the rear hitch raise rate switch to the ACM. Look for pinched wires, chafing, or corrosion at the connector terminals.

4. 4

   Circuit Testing

   Using a multimeter, verify continuity across the switch when actuated. Test the harness for shorts to ground or power.

5. 5

   Repair/Replace

   If the wiring harness is damaged, repair the broken wire or replace the harness section. If the wiring is intact but the switch fails the continuity test, the switch (or the integrated armrest control panel) has failed and must be replaced.

6. 6

   Reassembly and Clearing

   Reconnect the switch and ACM. Reconnect the battery. Use the Electronic Service Tool to clear the 518725-02 fault code, then operate the rear hitch raise rate switch to verify the repair.