Massey Ferguson E520220.31 – Engine Control Unit (Engine ECU): Engine Module Internal Issue (ECU) / MOCSOP (redundant stop test) Incorrect response time

The engine controller failed an internal safety and redundancy check. The ECU monitors the response time of the engine's shutdown circuit, and if the timing falls outside of the programmed safety parameters, it logs this internal error.

• 7616
• 5612
• 7622
• Interim Tier 4 (2012-2015)
• 7614
• 5611
• 7615
• 5610
• 5613
• 7620
• 5609
• 7618
• 5608
• 7619
• 7626
• 7624
• MF 5608
• MF 5609
• MF 5610
• MF 5611
• MF 5612
• MF 5613
• MF 7614
• MF 7615
• MF 7616
• MF 7618
• MF 7619
• MF 7620
• MF 7622
• MF 7624
• MF 7626

1. 1

   Verify the battery voltage is healthy and inspect the main power and ground feeds to the Engine ECU for corrosion, loose pins, or chafed wires.

2. 2

   Clear the fault codes using a diagnostic tool and perform a key cycle to determine if it is a hard internal fault.

3. 3

   Contact a dealer to check for an updated software flash for the Engine ECU that may widen the acceptable response time parameters for the MOCSOP test.

1. 1

   Disconnect Power

   Disconnect the tractor's battery (negative cable first) to prevent electrical spikes.

2. 2

   Locate the ECU

   Locate the Engine ECU, which is typically mounted directly to the side of the SisuDiesel/AGCO Power engine block on these models.

3. 3

   Remove the ECU

   Carefully release the locking levers on the main wiring harness connectors and unplug them from the ECU. Remove the mounting bolts securing the ECU to the engine block.

4. 4

   Install the New ECU

   Mount the replacement ECU and tighten the bolts. Reconnect the wiring harnesses, ensuring the locking levers are fully seated.

5. 5

   Reconnect Power

   Reconnect the battery cables.

6. 6

   Initialize/Program the ECU

   A blank or replacement Engine ECU must be initialized and programmed to the specific tractor using the Massey Ferguson EST (Electronic Service Tool) software. The tractor will not run until the immobilizer and engine parameters are synced by a dealer.