Massey Ferguson 30 – Air Conditioning Module (AIRCON): Issue With Signal To Right Cab Fan Speed Controller (AIRCON)

The climate control system is detecting an improper voltage, open circuit, or short circuit in the signal wire communicating with the right-side cab fan speed controller (commonly known as the blower motor resistor).

• 7724S
• Interim Tier 4 (2012-2015)
• 7722
• 7722S
• 7615
• 7720S
• 7716
• 7718
• 7726
• 7715
• 7616
• 7618
• 7619
• 7626
• 7726S
• 7624
• 7614
• 7718S
• 7620
• 7719
• 7714
• 7716S
• 7622
• 7720
• Tier 4 (2015-2021)
• 7715S
• 7724
• 4700 Series
• 4707
• 4708
• 4709
• 4710
• 5400 Series
• 5600 Series
• 5700 Series
• 5455
• 5610
• 5612
• 5711SL
• 5713SL
• 6400 Series
• 6600 Series
• 6480
• 6490
• 6615
• 7400 Series
• 7600 Series
• 7700 Series
• 7480
• 4300 Series
• 3000 Series
• 3600 Series
• 6100 Series
• 6200 Series
• 5710
• 5711

1. 1

   Test fan speeds: Check if the right cab fan operates on any speed. If it only works on the highest speed setting but fails on lower speeds, the speed controller (resistor) is almost certainly burnt out.

2. 2

   Check HVAC drainage: Inspect the HVAC negative pressure system mounted in the cab roof. Ensure drain hoses are clear, as clogged drain valves can cause condensation to pool and short out the fan speed controller.

3. 3

   Inspect wiring and connectors: Access the right fan speed controller and inspect the wiring harness for melted plastic, corroded pins, or loose connections caused by excessive amperage draw.

4. 4

   Test the blower motor: Check if the fan wheel is hard to spin by hand. A failing blower motor with worn bearings will have high electrical resistance and will repeatedly burn out new speed controllers.

1. 1

   Disconnect Power

   Turn off the tractor ignition and disconnect the negative battery cable to prevent electrical shorts.

2. 2

   Access the HVAC Unit

   Remove the necessary interior cab roof panels or headliner to access the HVAC blower assembly (location varies slightly by cab configuration, but is typically roof-mounted on these models).

3. 3

   Locate the Controller

   Locate the right cab fan speed controller (blower motor resistor) plugged into the side of the HVAC ducting/housing.

4. 4

   Remove the Faulty Unit

   Disconnect the electrical harness from the controller. Remove the retaining screws and pull the controller out of the housing.

5. 5

   Install the New Part

   Insert the new speed controller into the housing and secure it with the screws. Reconnect the electrical harness securely.

6. 6

   Reassemble and Test

   Reinstall the cab roof panels. Reconnect the battery. Turn the ignition on and test the right cab fan on all speed settings.

7. 7

   Clear Codes

   Use the tractor's dashboard diagnostic menu or a dealer diagnostic tool to clear the inactive 10.00.30 fault code.