Case IH 518862-02 - BCM – BCM: ATC water valve / heater control valve - permanent electrical defect

A communication failure or permanent electrical fault between the control module and the Automatic Temperature Control (ATC) actuator that regulates cab temperature (either the blend door actuator or the electronic heater water valve actuator).

• MAGNUM AFS Connect
• Magnum AFS Connect series
• Magnum 400
• Steiger / STX series
• STX 480
• STX 530
• Steiger 470 MY17 T4B CVT
• Puma series
• Puma 115
• Puma 180
• Puma 220
• Maxxum series
• Maxxum 125
• Axial-Flow Combines
• 7230
• 8230
• 9230

1. 1

   Inspect the wiring harness running from the BCM/ATC controller to the blend door actuator and heater control valve for a short to ground, short to power, or an open circuit.

2. 2

   Physically inspect the HVAC plenum, actuator motor, and louver/blend door for physical binding, debris, or structural damage.

3. 3

   Verify that the ATC unit is sending the correct voltage signals to the actuator.

1. 1

   Access the HVAC Plenum

   Remove the necessary cab interior panels to access the ATC controller and the HVAC plenum box.

2. 2

   Disconnect Electrical Connections

   Unplug the wiring harness from the faulty mode door motor / heater actuator.

3. 3

   Remove the Actuator

   Follow the 'ACTUATOR MOTOR AND LOUVER REMOVAL' procedure by unbolting the actuator from the HVAC housing.

4. 4

   Install the New Part

   Mount the new actuator or heater control valve assembly. Ensure the actuator aligns correctly with the blend door louver linkage.

5. 5

   Reconnect and Calibrate

   Reconnect the electrical harness. Turn on the machine and use the cab display or a diagnostic tool to clear the BCM fault codes. Cycle the temperature controls to verify the blend door and water valve operate smoothly without throwing a reception error.