Massey Ferguson AC23 – Air Conditioning Control Module: Fault with fan output for left-hand side fan

The system has detected an electrical irregularity (such as an open circuit, short circuit, or out-of-range resistance) in the circuit supplying power or signal to the left-hand side cab blower fan.

• 7616
• 5612
• 7622
• Interim Tier 4 (2012-2015)
• 7614
• 5611
• 7615
• 5610
• 5613
• 7620
• 5609
• 7618
• 5608
• 7619
• 7626
• 7624
• 7600 Series
• 7600 Dyna-4
• 7600 Dyna-6
• 7600 Dyna-VT
• 8600 Series
• MF 8670
• MF 8690

1. 1

   Inspect Module Connections: Locate the Air Conditioning Control Module and inspect the blue connector (X439) for loose pins, corrosion, or moisture.

2. 2

   Test the Relay: Locate the relay for the left-hand side fan (designated as X437). Test the relay for proper switching operation and check its socket for melted or corroded terminals.

3. 3

   Check the Fan Motor: Access the left-hand fan (X435). Disconnect it and apply direct 12V power to verify if the motor is seized or burnt out.

4. 4

   Inspect the Adapter Module: Check the left-hand fan adapter module (X445) and its supply line (X447) for proper voltage.

5. 5

   Check the Switch: Verify the integrity of the left-hand side fan switch (X436).

1. 1

   Power Down

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

2. 2

   Access the AC Module

   Remove the necessary interior cab trim panels to access the Air Conditioning Control Module.

3. 3

   Clean and Reseat

   Disconnect the blue connector (X439). Clean the contacts with electrical contact cleaner and reseat it firmly.

4. 4

   Relay Replacement

   If diagnostic checks proved the left-hand fan relay (X437) is faulty, pull the old relay from the fuse/relay board and install a new one.

5. 5

   Fan Motor Replacement

   If the fan motor (X435) failed the direct-power test, remove the HVAC housing cover on the left side of the cab roof, extract the faulty blower motor, and install the replacement.

6. 6

   Reassembly and Testing

   Reconnect the battery, turn the ignition on, and clear the stored AC23 fault code. Run the HVAC system on various fan speeds to confirm the left-hand fan is now operating correctly.