John Deere 157.02 – Engine Control Unit (ECU): The Fuel Rail Pressure Sensor Signal Voltage Out Of Range

The engine's control module is receiving invalid pressure data from the fuel rail pressure sensor. The sensor's input voltage is falling outside of the expected normal operating parameters, which can lead to incorrect fuel management, erratic engine behavior, or limited engine power.

• 5085E
• 5090E
• 5090EL
• 5100E
• 5065M
• 5075M
• 5085M
• 5100M
• 5100MH
• 5100ML
• 5115ML
• 5090M
• 5115M
• 6110M
• 6120M
• 6130M
• 6145M
• 6155M
• 6175M
• 6195M
• 6110R
• 6120R
• 6130R
• 6145R
• 6155R
• 6175R
• 6195R
• 6215R
• 5E Series
• 6R Series
• 8R Series
• 8RW Series
• 8245R
• 8400R
• 135D
• 450DLC
• 310SL
• 310J
• 310K
• 310L
• 450J
• 850J
• 544K
• 8225R
• 8320R
• S650
• S670

1. 1

   Inspect the wiring harness leading to the fuel rail pressure sensor for signs of chafing, damage, or short circuits.

2. 2

   Use a multimeter to measure the voltage at the sensor connector. Verify that the sensor is receiving the correct reference voltage from the ECU and that the signal wire is not shorted to a 12-volt source or ground.

3. 3

   Ensure there are no physical restrictions in the fuel system. Check fuel filters and lines (including orifice tee fittings) for blockages that could cause actual pressure anomalies mimicking a sensor failure.

1. 1

   Disconnect Power

   Turn off the machine and disconnect the battery to prevent electrical spikes.

2. 2

   Access the Sensor

   Locate the fuel rail pressure sensor on the engine's high-pressure fuel rail.

3. 3

   Repair Wiring

   If the diagnostic checks revealed damaged wiring or a bad connector, repair or replace the affected section of the harness.

4. 4

   Replace the Sensor

   If the wiring is intact and the voltage is out of range due to an internal sensor failure, carefully unscrew the old fuel rail pressure sensor. Install the new OEM sensor and torque it to the manufacturer's specifications.

5. 5

   Reassemble and Reconnect

   Plug the electrical connector back into the new sensor and reconnect the battery.

6. 6

   ECU Reset

   Use a diagnostic scan tool to clear the 000157.02 fault code from the ECU.

7. 7

   Test Run

   Start the engine and monitor the fuel rail pressure via the diagnostic tool to ensure the new sensor is reading within the normal range and the code does not return.