Massey Ferguson 520219.31 – Engine Control Unit (ECU) / AGCO SISU POWER EEM3 or EEM4: ECU internal fault 0112 (MoCSOP - Test of redundant shut-off paths)

The controller detected an internal hardware failure, a response time error, or too many SPI (Serial Peripheral Interface) errors while testing the engine's redundant safety shut-off circuits during the MoCSOP (Test of redundant shut-off paths).

• 4710
• 7724S
• 5712SL
• Interim Tier 4 (2012-2015)
• 7722
• 7722S
• 7615
• 5613
• 5713SL
• 7720S
• 7716
• 7718
• T4
• 7715
• 5710SL
• 7726
• 7616
• 7618
• 5608
• 4708
• 7619
• 7626
• 7726S
• 7624
• 4707
• 4709
• 5711SL
• 7614
• 7718S
• 5610
• 7620
• 7719
• 7714
• 7716S
• T4 (2015-2021)
• 5612
• 7622
• 7720
• Tier 4 (2015-2021)
• 5611
• 7715S
• 5609
• 7724
• 7700 series

1. 1

   Check for Injector Faults: Diagnose and repair any active injector short-circuit codes first, as an injector problem can sometimes cause the redundant shut-off path test to fail.

2. 2

   Cycle and Retest: Clear the fault codes using the AGCO Electronic Service Tool and cycle the ignition, as the redundant shut-off paths are monitored once every driving cycle.

3. 3

   Verify Voltage: Ensure battery voltage to the ECU is stable, as severe undervoltage during the MoCSOP test can sometimes trigger internal fault logic.

1. 1

   Disconnect battery

   Disconnect the tractor's battery (negative terminal first) to prevent electrical arcing.

2. 2

   Locate ECU

   Locate the Engine Control Unit (EEM3/EEM4 module) typically mounted on or near the engine block.

3. 3

   Disconnect harnesses

   Carefully disconnect the primary and secondary wiring harness connectors from the ECU.

4. 4

   Remove ECU

   Unbolt and remove the faulty ECU from its mounting bracket.

5. 5

   Install replacement ECU

   Install the replacement ECU and secure the mounting bolts.

6. 6

   Reconnect harnesses

   Reconnect the wiring harnesses, ensuring the locking mechanisms click into place.

7. 7

   Reconnect battery

   Reconnect the battery.

8. 8

   Program ECU

   Connect the AGCO Electronic Service Tool to the machine's diagnostic port. The new ECU must be flashed/programmed with the correct software and fuel maps for your specific tractor model and engine serial number.

9. 9

   Verify repair

   Run the engine and verify that the MoCSOP test passes and the fault code does not return.