Case IH 519667-12 - BCM – BCM: ATC rear vent door actuator permanent electrical defect

The module has lost communication with or detected an unrecoverable internal short/open in the actuator motor or its potentiometer.

• MAGNUM AFS Connect
• Puma
• Magnum
• Steiger
• Axial-Flow series
• Patriot Sprayers

1. 1

   Inspect the wiring harness and connectors between the rear vent door actuator and the BCM for physical damage, chafing, or loose connections.

2. 2

   Verify that the actuator is receiving the correct power supply and has a solid ground.

3. 3

   Test the data signal circuit to ensure the BCM is capable of processing the sensor data correctly and that the wiring is not shorted.

4. 4

   Test the BCM/ATC controller for potential processing errors to rule out a module failure.

1. 1

   Disconnect battery power

   Disconnect battery power to the machine to prevent electrical shorts.

2. 2

   Gain access to HVAC distribution box

   Gain access to the rear HVAC distribution box (typically located in the cab roof or rear cab panel, depending on the machine model).

3. 3

   Disconnect electrical harness

   Disconnect the electrical harness from the faulty rear vent door actuator.

4. 4

   Remove mounting screws

   Remove the mounting screws securing the actuator to the blend door linkage.

5. 5

   Install new actuator

   Install the new actuator, ensuring the mechanical linkage aligns correctly with the vent door.

6. 6

   Reconnect harness and restore power

   Reconnect the electrical harness and restore battery power.

7. 7

   Clear fault code

   Clear the fault code from the BCM using a diagnostic scan tool.

8. 8

   Restart and calibrate system

   Restart the system and cycle the ATC temperature/vent settings to confirm the fix and allow the system to calibrate the new actuator's position.