Case IH 518597-02 - ACM – ACM: Front/rear hitch selector switch circuit fault

The control system is detecting an open circuit, a short circuit (to ground or power), or an implausible voltage reading from the switch that toggles control between the front and rear hitches.

• MAGNUM AFS Connect
• Magnum 235
• Magnum 290
• Magnum 315
• Magnum 340
• Steiger 350
• Steiger 400
• Steiger 500
• Steiger 600
• Puma 165
• Puma 180
• Puma 195
• Puma 200
• Puma 210
• Puma 225
• Maxxum 5230
• Maxxum 5240
• CVX 140
• CVX 150
• CVX 160
• CVX 175
• CVX 195

1. 1

   Check ACM Configuration: Use the Case IH Electronic Service Tool (EST) to verify that the ACM is correctly configured for the specific hitch setup (e.g., verifying the parameters for 'Rear hitch raise switch', 'Rear hitch lower switch', and front hitch presence).

2. 2

   Inspect the Switch Mechanically: Check if the hitch selector switch is physically stuck, damaged, or pressed simultaneously with another conflicting switch.

3. 3

   Wiring and Circuit Test: Inspect the wiring harness connecting the hitch switch to the Armrest Control Module. Look for chafed wires, loose pins, or corrosion at the connectors.

4. 4

   CAN Communication Check: Verify the CAN bus communication to the ACM. Check termination resistors, network connections, and ensure there is no loss of communication with the instrumentation controller.

1. 1

   Power Down

   Turn off the tractor and disconnect the battery to prevent electrical shorts or static electricity damage to the sensitive armrest electronics.

2. 2

   Access the ACM Console

   Carefully remove the trim panels on the armrest console to access the Armrest Control Module and the integrated switch panels.

3. 3

   Disconnect the Switch

   Locate the front/rear hitch selector switch and disconnect its electrical connector (e.g., the 34-cavity ACM CN1 connector or the specific switch pigtail).

4. 4

   Test the Switch

   Use a multimeter to test the switch for proper continuity across its positions. If the switch shows an open circuit when closed or erratic resistance, it has failed internally.

5. 5

   Replace the Switch

   Remove the mounting screws or retaining clips holding the faulty switch in the armrest panel. Insert the new switch and secure it.

6. 6

   Reassembly

   Reconnect the wiring harness, ensuring the terminal pins are fully seated. Reinstall the armrest console panels.

7. 7

   Recalibrate

   Reconnect the battery, power on the tractor, and use the EST diagnostic tool to clear the fault code. You may need to recalibrate the hitch controls or potentiometers so the ACM recognizes the new switch inputs.