Massey Ferguson E520240.31 – Engine Control Unit (ECU) / AGCO SISU POWER EEM3 or EEM4: Injector bank 0 short circuit

The engine management system has detected a short circuit in the electrical circuit controlling the fuel injectors on Bank 0. This can be caused by a damaged wiring harness, an internally shorted fuel injector, or an internal failure within the engine controller's power stage.

• 7616
• 5612
• 7622
• Interim Tier 4 (2012-2015)
• 7614
• 5611
• 7615
• 5610
• 5613
• 7620
• 5609
• 7618
• 5608
• 7619
• 7626
• 7624
• 33 series
• 44 series
• 49 series
• 66 series
• 74 series
• 84 series
• 98 series
• 7600 Series

1. 1

   Turn the ignition off and wait at least 2 minutes for the ECU to power down, then disconnect the negative battery cable and the EEM4 control unit main connector.

2. 2

   Visually inspect the injector wiring harness for Bank 0 (routing from the ECU to the injectors) for chafed wires, melted insulation, or pinched areas, especially under the valve mechanism cover.

3. 3

   At the injector harness ECU connector, measure the resistance between the solenoid valve contact pins for Bank 0 and the engine ground to check for a short circuit.

4. 4

   Disconnect the harness from the individual injectors on Bank 0 and test the resistance across the injector terminals using a multimeter to rule out an internal short inside the injector solenoid.

5. 5

   Check the pins on the EEM4 ECU and the harness connectors for corrosion, moisture, or bent pins.

1. 1

   Power Down

   Turn off the tractor, wait 60 seconds to 2 minutes for the system to reset/power down, and disconnect the battery.

2. 2

   Access the Harness

   Remove the valve mechanism cover if the engine utilizes an internal injector harness, or trace the external harness to Bank 0.

3. 3

   Repair/Replace Wiring

   If the diagnostic checks reveal a short in the wiring, repair the damaged section of the harness or replace the entire injector harness assembly. Ensure the new harness is routed correctly so it does not contact the valve cover.

4. 4

   Replace Faulty Injectors

   If the wiring tests good but an injector fails the resistance test, remove and replace the faulty fuel injector.

5. 5

   ECU Replacement

   If both the wiring harness and the injectors are in good working order, the fault is likely an internal failure of the ECU (such as a CY33X power stage component failure). You will need to replace the EEM4 unit. Note: A new ECU must be programmed and calibrated (IQA codes) using the AGCO Electronic Diagnostic Tool (EDT) or WinEEM4 software.

6. 6

   Reassembly and Clearing Codes

   Reconnect all components and the battery. Turn the ignition on and use the AGCO EDT to clear the inactive fault codes and verify the repair.