Massey Ferguson 10.X.15 – AIRCON: Air Vent Circulation Flap Position Sensor Supply Voltage Issue (AIRCON)

The HVAC system uses an electronic actuator motor to move the air circulation flap (blend door/recirculation door). This actuator contains a built-in position sensor (potentiometer) that reports the flap's physical position back to the controller. This fault code indicates that the supply voltage to this position sensor is out of the expected operating range. Without the correct voltage, the controller cannot determine the flap's position, which usually results in the HVAC system failing to switch between fresh air and recirculated air, or failing to blend temperatures correctly.

• 7724S
• 5712SL
• 7722
• 7722S
• 5713SL
• 7720S
• 7716
• 7718
• T4
• 7715
• 5710SL
• 7726
• 7726S
• 5711SL
• 7718S
• 7719
• 7714
• 7716S
• 7720
• Tier 4 (2015-2021)
• 7715S
• 7724
• 4700 Series
• 4707
• 4708
• 4709
• 4710
• 5600 / 5700 Series
• 5608–5613
• 5710SL–5713SL
• 6700 Series
• 6711
• 6712
• 6713
• 7600 / 7700 Series
• 7614–7626
• 7714–7726S
• 8600 / 8700 Series

1. 1

   Using a multimeter, probe the connector at the circulation flap actuator to verify that the AC module is sending the correct reference voltage (typically 5V) to the sensor.

2. 2

   Trace the wiring harness from the flap actuator back to the AIRCON module. Look for chafed wires, pinched harnesses, or rodent damage that could short the supply voltage to ground.

3. 3

   Disconnect the actuator and inspect the pins on both the harness side and the sensor side for pushed-out pins, corrosion, or moisture ingress.

4. 4

   If the wiring and supply voltage from the module are intact, test the internal potentiometer of the flap actuator, as it has likely failed or shorted internally.

1. 1

   Power Down

   Turn off the tractor and disconnect the negative battery terminal to prevent electrical shorts during repair.

2. 2

   Access the HVAC Unit

   Depending on the tractor model, the HVAC unit is typically located either in the cab roof canopy or under the dashboard/console. Remove the necessary interior trim panels or roof cap to access the HVAC housing.

3. 3

   Locate the Actuator

   Identify the air vent circulation flap actuator on the side of the HVAC air box.

4. 4

   Remove the Actuator

   Disconnect the electrical connector from the actuator. Remove the mounting screws (usually 2 or 3 small Torx or Phillips screws) holding the actuator to the HVAC housing. Pull the actuator straight off the blend door shaft.

5. 5

   Install the New Part

   Align the splines/shaft of the new actuator with the flap door and press it into place. Secure it with the mounting screws.

6. 6

   Reassembly

   Reconnect the electrical connector, reassemble the cab trim/roof panels, and reconnect the battery.

7. 7

   Clear Codes & Calibrate

   Use the AGCO Electronic Diagnostic Tool (EDT) or the tractor's dash interface to clear the 10.X.15 fault code. Cycle the HVAC controls through all modes to allow the AC module to learn the end-stops of the new actuator.