John Deere 157.17 – Engine Control Unit (ECU): Fuel Rail Pressure Not Developed

The Engine Control Unit (ECU) cannot detect the required minimum fuel rail pressure of 10 MPa (100 bar or 1450 psi) after the engine has been cranking or running for approximately 3 to 5 seconds. The engine is not receiving adequate fuel pressure, which will cause the engine to fail to start, stall, or operate with severely limited power.

• 5085E
• 5090E
• 5090EL
• 5100E
• 5065M
• 5075M
• 5085M
• 5100M
• 5100MH
• 5100ML
• 5115ML
• 5095M
• 5095MH
• 5105M
• 5015ML
• 5090M
• 5115M
• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 7810
• 9230
• 9330
• 9430
• 9530
• 9630
• 370E
• 410E
• 460E
• 450J
• 648H
• 250GR
• 7760
• 3520

1. 1

   Check Fuel Level: Verify that the fuel tank is not empty or critically low, causing the pump to draw air.

2. 2

   Check System Prime: Ensure the fuel system is properly primed. If the system was recently serviced or ran out of fuel, air in the lines will prevent pressure development.

3. 3

   Inspect Fuel Filters: Check the primary and secondary fuel filters for severe clogs, restrictions, or water contamination.

4. 4

   Inspect Fuel Lines: Look for collapsed supply lines, pinched hoses, or external fuel leaks that could impede pressure development.

1. 1

   Prime the Fuel System

   Manually prime the fuel system to bleed out any trapped air. Attempt to crank the engine.

2. 2

   Replace Fuel Filters

   If filters have not been serviced recently, replace them to rule out a flow restriction.

3. 3

   Test the Fuel Pump / Suction Control Valve

   Verify that the fuel lift pump is operational and supplying adequate low-pressure fuel to the high-pressure injection pump. Evaluate the fuel pump suction control valve (pressure regulator) for faults or sticking.

4. 4

   Test the Fuel Rail Pressure Sensor

   Use a diagnostic scan tool (like John Deere Service ADVISOR) to monitor live fuel rail pressure data while cranking. If the physical pressure is verified with a mechanical gauge but the sensor reads 0, the sensor or its wiring harness is faulty.

5. 5

   Replace Faulty Components

   Replace the fuel pressure regulator, high-pressure fuel pump, or fuel rail pressure sensor based on the diagnostic test results.

6. 6

   Clear Codes and Verify

   Reset the ECU using a diagnostic tool. Crank the engine and verify that the fuel rail pressure reaches and maintains the required 10 MPa (1450 psi) threshold within 3 seconds.