Case IH 2666-02 - ACM – ACM: Joystick y-axis lever forward positive position status circuit fault

The control system has detected an electrical anomaly (such as a short circuit, open circuit, or out-of-range voltage) in the circuit that monitors the forward (positive) movement of the joystick's Y-axis.

• MAGNUM AFS Connect
• Case IH Magnum AFS Connect
• Case IH Magnum Series
• Case IH Puma Series
• Case IH Maxxum Series
• Case IH Optum Series
• Case IH Steiger Series

1. 1

   Verify ACM Configuration using the Electronic Service Tool (EST) to ensure incorrect configuration isn't falsely triggering the fault

2. 2

   Monitor the Y-axis position voltages for signals indicating voltage too low, voltage too high, or an open/short circuit

3. 3

   Inspect the wiring harness and connectors between the joystick assembly and the ACM for continuity, pinched wires, open circuits, or shorts to ground/battery

4. 4

   Check for loss of communication between the ACM and the instrumentation controller

1. 1

   Connect diagnostic tool

   Connect the CNH Electronic Service Tool (EST) to the machine's diagnostic port to confirm 2666-02 is active and review any freeze-frame data.

2. 2

   Verify configuration

   Navigate to the ACM configuration menu to ensure the correct joystick type is programmed for the tractor.

3. 3

   Inspect connector

   Disconnect the multi-pin CNH plug at the base of the joystick. Inspect the pins for corrosion, moisture, or damage.

4. 4

   Test wiring harness

   Use a multimeter to test the wiring harness from the joystick connector back to the Armrest Control Module (ACM) for continuity and shorts.

5. 5

   Diagnose joystick failure

   If the wiring harness tests good and the ACM is configured correctly, the internal Y-axis potentiometer/sensor inside the joystick has failed.

6. 6

   Remove faulty joystick

   Remove the armrest control panel trim and unbolt the faulty joystick assembly.

7. 7

   Install replacement joystick

   Install the replacement joystick, reconnect the harness, and reassemble the armrest.

8. 8

   Clear codes and calibrate

   Clear the fault codes using the EST and perform a joystick calibration procedure to map the new X and Y axis limits to the ACM.