Case IH 18352 (1083.02, 1083.03, 1083.04, 2686.02, 2686.03, 2686.04, 2686.07) - ACML – Armrest Control Module (ACML): Joystick Button 2 ACML - error state

The control module is receiving an invalid electrical signal from Button 2 on the Multi-Function Handle (joystick). Depending on the specific FMI extension, the underlying condition is typically a voltage that is too high (short to power), a voltage that is too low (short to ground), an open circuit, or an erratic/incorrect signal from the button's microswitch.

• MAXXUM T4E
• VESTRUM CVX
• Case IH Magnum Series (e.g., 235, 260, 290, 340)
• Case IH Steiger / Quadtrac Series (e.g., 500, 550, 580, 620)
• Case IH Puma Series (e.g., 200)
• Case IH Maxxum Series (e.g., 135 Multicontroller Activedrive 8)
• Case IH Vestrum CVXDrive

1. 1

   Visual & Mechanical Inspection: Check the physical condition of Joystick Button 2 on the Multi-Function Handle. Ensure the button is not physically stuck, jammed with debris, or mechanically broken.

2. 2

   Configuration Check: Verify the configuration of the ACML using a diagnostic tool. Incorrect configuration of the ACM can sometimes falsely trigger joystick axis or button faults.

3. 3

   Wiring & Harness Test: Disconnect the electrical connector at the base of the joystick and at the ACML. Perform a continuity test on the circuit for Button 2. Check for shorts to ground or shorts to battery power.

4. 4

   Active vs. Stored Faults: Clear the fault code with a diagnostic tester. Actuate Button 2 to see if the code immediately returns (indicating a hard electrical failure) or if it was an intermittent stored fault.

1. 1

   Power Down

   Turn off the tractor and disconnect the battery ground cable to prevent electrical spikes during module handling.

2. 2

   Access the Armrest Internals

   Remove the retaining screws and plastic trim panels on the multicontroller armrest to expose the wiring harness for the Multi-Function Handle and the ACML.

3. 3

   Isolate the Component

   If the wiring harness tested good during diagnostics, the fault is isolated to either the joystick assembly itself or the ACML.

4. 4

   Replace the Joystick

   Internal button failures on the Multi-Function Handle usually cannot be serviced individually. Disconnect the main harness plug for the joystick, unbolt the handle assembly from the armrest base, and install the replacement Multi-Function Handle.

5. 5

   Replace the ACML

   If the joystick is proven functional but the module fails to read the input, replace the Armrest Control Module. Unplug the multi-pin connectors from the ACML and swap the unit.

6. 6

   Reassembly & Calibration

   Reconnect the battery. Connect the diagnostic tester, clear the original fault codes, and perform any required joystick/armrest calibration procedures as prompted by the software.