Massey Ferguson 520382.02 – Engine Control Unit (ECU): Issue With The Air Intake Mass Air Flow Sensor

The sensor is sending a reading to the controller that does not logically match the engine's current operating parameters (e.g., RPM, boost pressure, and throttle position), or the sensor itself has failed internally. The signal is 'not plausible' or has an 'inconsistent voltage'.

• 4710
• 7724S
• 5712SL
• 7722S
• 7722
• 5713SL
• 7720S
• 7716
• 7718
• T4
• 7715
• 5710SL
• 7726
• 4708
• 7726S
• 4707
• 4709
• 5711SL
• 7718S
• 7719
• 7714
• 7716S
• T4 (2015-2021)
• 7720
• Tier 4 (2015-2021)
• 7715S
• 7724
• MF 6400
• MF 7400
• MF 7600
• MF 8700 S
• 8727 S
• 8730 S
• 8732 S
• 8735 S
• 8737 S
• 8740 S
• MF IDEAL 7
• MF IDEAL 8
• MF IDEAL 9
• Beta 7370
• MF WR Series
• WR 9735
• WR 9740
• WR 9760

1. 1

   Inspect the Air Filter: Check the air filter restriction indicator and inspect the primary and secondary filters for severe clogs that can restrict airflow.

2. 2

   Check for Intake Leaks: Inspect the air intake piping between the air filter housing, the MAF sensor, and the turbocharger for cracks, loose clamps, or unmetered air entering the system.

3. 3

   Inspect the Wiring Harness: Check the MAF sensor's electrical connector for moisture, corrosion, or pushed-back pins.

4. 4

   Verify Voltage: Test the sensor pigtail for proper 5V reference voltage and a solid ground from the Engine ECU.

1. 1

   Power Down

   Turn off the engine, remove the key, and turn off the battery disconnect switch to prevent electrical spikes to the ECU.

2. 2

   Locate the Sensor

   Find the MAF sensor, which is mounted in the path of the incoming engine air, directly between the air filter housing and the turbocharger inlet.

3. 3

   Disconnect Wiring

   Gently bend the locking tab out slightly and unplug the factory wiring harness connector from the sensor.

4. 4

   Remove the Sensor

   Remove the retaining screws (usually Torx or Allen head) securing the MAF sensor to the intake pipe housing. Pull the sensor straight out.

5. 5

   Clean and Prep

   Wipe the mounting port on the intake pipe with a clean, lint-free cloth to ensure a good seal.

6. 6

   Install the New Sensor

   Insert the replacement MAF sensor, ensuring the O-ring is properly seated so no unmetered air can bypass it.

7. 7

   Secure and Reconnect

   Tighten the retaining screws and plug the electrical connector back in until the lock tab clicks.

8. 8

   Clear Codes

   Reconnect the battery, turn the key on, and use a diagnostic scan tool to clear the 520382.02 fault code from the Engine ECU.