Case IH 3107 (DTC 6655) - ECU – Engine Electronic Control Unit (ECU A-095): Fuel metering unit is shorted to battery voltage at the low side.

The power stage of the fuel metering unit (designated as component Y-011) is monitored for electrical failures. The control module has detected a short circuit to a high voltage source (battery voltage) on the low side (ground/control side) of the fuel metering unit's circuit.

• MAXXUM T4E
• Case IH Puma series
• Case IH Magnum series (MX210, MX230, MX255, MX285)
• Case IH Steiger models
• 240 Series Axial-Flow Combines
• A8000 Sugar Cane Harvester
• A8800 Sugar Cane Harvester

1. 1

   Check System Voltage: Verify the battery voltage on the instrument cluster or with a multimeter to ensure the charging system is not overcharging or providing abnormal voltage.

2. 2

   Inspect the Wiring Harness: Check the wiring harness between the Engine ECU (A-095) and the Fuel Metering Unit (Y-011). Look for chafing, melted insulation, or pinched wires that could cause the low-side circuit to short to a 12V power source.

3. 3

   Test the Circuit: Disconnect the fuel metering unit connector. With the key ON, probe the low-side terminal on the harness. If battery voltage is present, the wiring harness is shorted and must be repaired.

4. 4

   Test the Solenoid: If the harness is intact, check the internal resistance of the fuel metering unit solenoid across its terminals to determine if the component itself has failed internally.

1. 1

   Disconnect Power

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

2. 2

   Repair Wiring (If Applicable)

   If the diagnostic checks revealed a short in the wiring harness between the ECU and the fuel metering unit, repair or replace the damaged section of the harness.

3. 3

   Locate the Component

   If the wiring is fine and the unit itself is faulty, locate the fuel metering unit (Y-011), which is mounted directly on the high-pressure fuel injection pump.

4. 4

   Remove the Faulty Unit

   Disconnect the electrical connector from the fuel metering unit. Remove the mounting fasteners securing it to the high-pressure pump and carefully pull the unit out.

5. 5

   Prepare the New Unit

   Lubricate the O-rings on the new fuel metering unit with clean diesel fuel to prevent tearing during installation.

6. 6

   Install

   Insert the new fuel metering unit into the pump. Install and tighten the mounting fasteners to the manufacturer's specified torque.

7. 7

   Reconnect

   Plug the electrical connector back into the unit and reconnect the battery.

8. 8

   Clear Codes and Test

   Use a diagnostic tool to clear the 3107 (DTC 6655) fault code. Start the engine, check for fuel leaks around the pump, and verify that the engine operates without triggering a warning light or power loss.