Fuel Level Sensor Circuit Failure
Indicates a fault in the fuel level sensor circuit.
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What it means (plain English)
The fuel level sensor is not sending the correct data to the engine computer, which means the computer doesn't know how much fuel is in the tank.
What the computer is actually seeing
The engine control module expects the fuel level sensor to provide a voltage between 0.5V (empty) to 4.5V (full). If the voltage is outside this range or not changing properly, a fault code is triggered.
What a healthy reading looks like
Normal fuel level sensor should provide a voltage signal ranging from 0.5V to 4.5V depending on the fuel level.
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. Inspect the wiring and connectors at the fuel level sensor for visible damage or corrosion. Fix any issues found.
- 22. Measure the voltage at the fuel level sensor connector with the ignition on (engine off). Expect a voltage between 0.5V to 4.5V.
- 3 - If voltage is out of range, suspect a faulty sensor or damaged wiring. Go to step 3.
- 4 - If voltage is normal, check the engine control module's ground and power supply. If okay, consider a software issue.
- 53. With the wiring intact, replace the fuel level sensor and recheck the voltage. Confirm it operates within the expected range.
Common causes
- Faulty fuel level sensor
- Corroded or damaged wiring to the sensor
- Bad connector pins or connectors
- Short circuit in the fuel level sensor circuit
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's drivable but you'll have inaccurate fuel readings, which can lead to running out of fuel unexpectedly.
Will this code come back after clearing it?
If the underlying issue isn't fixed, yes, the code will return.
Why does this code pair with SPN 597?
SPN 597 is related to the same fuel level system and indicates the sensor's signal is out of range, often occurring alongside SPN 596.
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