John Deere 1075.04 – Engine Control Unit (ECU): Low Pressure Fuel Pump Supply Voltage Low

The Engine Control Unit (ECU) has detected a low supply voltage to the electric low-pressure fuel pump. This condition impedes the proper function of the fuel pump, leading to inadequate fuel pressure being delivered to the high-pressure fuel system. Consequences of this fault can include hard starting, extended cranking, loss of engine power, and the engine entering a derated limp mode to prevent damage.

• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 8245R through 8400R
• 8310RT
• 8335RT
• 8360RT
• 9470RT
• 9520RT
• 9570RT
• 7180
• 7280
• 7380
• 7480
• 7580
• 7780
• 7980

1. 1

   Check for active DTCs to ensure no other related codes point to a broader electrical failure

2. 2

   Visually inspect the wiring harness and connectors between the low-pressure fuel pump and the ECU for signs of damage, corrosion, or loose connections

3. 3

   Use a multimeter to verify the supply voltage at the pump connector (must be above 9V) and check the circuit for a short to ground (low source)

4. 4

   Verify the ECU software is up-to-date, as software glitches can sometimes mimic hardware failures

1. 1

   Address Wiring Faults

   If the diagnostic checks reveal damaged wires, corroded connectors, or a short to ground, repair or replace the affected wiring harness/terminals to restore proper circuit continuity and voltage.

2. 2

   Replace the Fuel Pump

   If the wiring is intact and providing proper voltage but the pump has an internal short or failure, replace the electric low-pressure fuel pump. (Note: Do not pressurize the fuel tank during testing or repair, as this can rupture the high-pressure pump seal and fill the crankcase with fuel).

3. 3

   Reset the ECU

   After repairs are made, cycle the ignition key or use a diagnostic tool to reset the ECU and clear the error code.

4. 4

   Verify Operation

   Test run the engine and verify that the fuel pump operates correctly, fuel pressure is restored, and the 001075.04 code does not return.