Fuel Level Sensor 1 - Invalid Reading
The fuel level sensor is sending a reading that cannot be interpreted by the controller.
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 level sensor is supposed to measure how much fuel is in the tank, but it's sending back weird numbers that don't make sense to the engine control module (ECM).
What the computer is actually seeing
The ECM expects the fuel level sensor to provide a voltage signal between 0.5V (empty) and 4.5V (full). If it sees a stably incorrect voltage (like 0.0V or over 4.5V), it throws this code.
What a healthy reading looks like
Signal voltage should be between 0.5V (empty) and 4.5V (full).
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.
- 1Check the wiring and connector to the fuel level sensor for damage or corrosion.
- 2Measure the voltage at the fuel level sensor while the engine is running. You should see it vary between 0.5V and 4.5V as the fuel level changes.
- 3If the voltage is correct, check the ECM for software updates or faults that may be causing bad readings. If it's not correct, replace the fuel level sensor.
Common causes
- Faulty fuel level sensor
- Wiring issues or broken connectors
- ECM programming error
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
Yes, but keep an eye on fuel levels and refuel as needed.
Will this code come back after clearing it?
If the underlying issue isn't fixed, the code will likely return.
Why does this code pair with SPN 2518 or SPN 2520?
These codes also relate to fuel system sensing issues, often triggered by the same faults.
Working a real vehicle right now?
Let DiagCoach walk you through it live with your specific symptoms, vehicle, and what you've already checked.
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