Fuel Pressure Sensor Circuit Low
Fuel pressure sensor is reporting a low voltage signal.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The fuel pressure sensor sends a voltage signal to the engine control module (ECM) that reflects the pressure in the fuel system. If this voltage is below a certain threshold (typically around 0.5 volts), the ECM thinks there's a problem with the pressure being too low.
What the computer is actually seeing
The ECM monitors the fuel pressure sensor input expecting a voltage between 0.5 to 4.5 volts under normal operating conditions. When the signal drops below 0.5 volts, it triggers SPN 273.
What a healthy reading looks like
Fuel pressure should be between 30 to 70 psi depending on the vehicle, and the sensor should output between 0.5 to 4.5 volts to reflect this pressure.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Check for any visible wiring damage or loose connectors related to the fuel pressure sensor. If found, repair or tighten first.
- 22. Verify fuel level is sufficient. If low, fill the tank before further diagnosis.
- 33. With the key on (engine off), measure the voltage at the fuel pressure sensor wiring harness. It should be between 0.5 to 4.5 volts. If not, repair the wiring accordingly.
- 44. If wiring is good, start the engine and again measure the voltage at the sensor while the engine is running. If it remains below 0.5 volts, replace the fuel pressure sensor. If it is within normal range, further investigate fuel delivery issues like pump performance.
Common causes
- Faulty fuel pressure sensor
- Wiring issues (shorts or open circuit)
- Corrosion in connectors
- Low fuel level
- Faulty fuel pump
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's safe to drive for a short while, but performance may be impacted, and it's best to fix it soon.
Will this code come back after I fix it?
If the issue is fixed properly, the code should not come back.
Why does this code trigger with other codes?
This code often appears with other fuel system-related codes because they are interconnected in monitoring fuel pressure.
Working a real vehicle right now?
Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.
Start guided diagnostic →