New Holland 3137 – Engine ECU: Fuel Metering Unit: Open Load of Metering Unit Output

The engine control module has detected an open circuit in the output of the Fuel Metering Unit that has persisted for more than 200 milliseconds. This indicates a potential issue with the electrical connection or the unit itself, preventing the ECU from controlling the solenoid valve that regulates the volume of fuel entering the high-pressure pump. This condition can cause the engine to crank but not start, experience hard starting, stall under load, lose acceleration, or enter limp mode.

• T6 Series
• T6.155
• T7 Series
• T7.210
• T7.270
• T7030
• T7040
• T7050
• T7060
• T9000 Series
• T9030
• Puma Series
• Puma 115-230
• Magnum Series

1. 1

   Verify the fault code is active using an Electronic Service Tool (EST) and check for any other related codes. Note the fault's occurrence and the engine hours.

2. 2

   Check battery voltage to ensure it is fully charged (above 12.1V) and verify that all main power and ground connections to the chassis and ECU are clean and tight.

3. 3

   Visually inspect the wiring harness and connectors between the Engine Control Unit (ECU) and the Fuel Metering Unit on the high-pressure pump for chafing, corrosion, broken wires, or loose pins.

4. 4

   Disconnect the electrical connector from the Fuel Metering Unit and measure the resistance across its two pins. A normal reading is approximately 3.2 Ohms; a significantly higher reading (or infinite resistance) indicates an open circuit within the solenoid.

5. 5

   Check for continuity on the wiring harness from the ECU connector to the Fuel Metering Unit connector to identify any breaks.

6. 6

   Check the wiring harness for any shorts to ground or to a power source.

1. 1

   Ensure safety

   Before working on the high-pressure fuel system, ensure the engine is off and has had time to cool down to prevent serious injury from high-pressure fuel.

2. 2

   Clear codes and test

   Use an electronic service tool to clear all fault codes from the ECU's memory. Start the engine and run it under normal conditions. If the fault does not reappear, the issue may have been an intermittent poor connection.

3. 3

   Component Testing

   If the fault returns, proceed with the electrical tests outlined in the diagnostic checks.

4. 4

   Repair wiring harness

   If electrical testing reveals a break or short in the wiring harness between the ECU and the Fuel Metering Unit, repair or replace the affected section.

5. 5

   Replace Fuel Metering Unit

   If the resistance test across the Fuel Metering Unit solenoid pins shows a significantly higher reading than 3.2 Ohms or infinite resistance (indicating an open coil), replace the solenoid.

6. 6

   Final verification

   After repair or replacement, clear any fault codes and run the vehicle to ensure the issue is fully resolved.