Massey Ferguson 520242.31 – Engine Control Unit (ECU): Injector bank 2 short circuit

The engine management system has detected a short circuit condition on the wiring circuit that controls the fuel injectors grouped in 'Bank 2'. The Failure Mode Identifier (FMI) 31 indicates that the condition exists or that the signal is out of range/unreliable.

• 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
• Massey Ferguson tractors and agricultural equipment powered by AGCO Power (formerly SisuDiesel) engines

1. 1

   Perform a system reset by turning the ignition off for a minimum of 60 seconds, then turn it back on to see if the code clears or returns as an active fault.

2. 2

   Inspect the injector wiring harness for Bank 2 for visible signs of chafing, melted insulation, or pinched wires that could cause a short to ground or a short to the battery.

3. 3

   Disconnect the injector connectors on Bank 2 and the ECU. Check for loose, bent, pushed-out, or corroded pins.

4. 4

   Use a multimeter to measure the resistance of the wiring harness to check for continuity to ground.

5. 5

   Measure the resistance of each individual injector on Bank 2 to identify if an injector solenoid has failed and shorted internally.

1. 1

   Turn off the machine and disconnect the negative battery terminal to prevent electrical damage.

2. 2

   Locate the Bank 2 injectors and trace the associated wiring harness back to the Engine ECU.

3. 3

   Disconnect the wiring harness from the Bank 2 injectors and the ECU.

4. 4

   If a short is found in the wiring harness during your multimeter continuity testing, carefully open the loom to repair the damaged section of the wire, or replace the entire injector wiring harness if the damage is extensive.

5. 5

   If the harness tests fine but an injector tests out of specification (internally shorted), remove the faulty injector and replace it with a new OEM injector.

6. 6

   Reconnect all harnesses securely, ensuring all connectors click into place and are free of moisture.

7. 7

   Reconnect the battery.

8. 8

   Turn the ignition on and use a diagnostic service tool (such as the WinEEM3 or EEM4 Service Tool) to clear the stored DTC codes.

9. 9

   Start the engine and verify that the fault code does not return and that the engine operates without power degradation.