FUEL LEVEL INDICATOR ACTIVE (LAMP TEST)
Indicates an issue with the fuel level sensor reading.
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 not giving the right readings about how much fuel is in the tank. This could lead to running out of fuel unexpectedly or overfilling.
What the computer is actually seeing
The engine control module monitors the fuel level readings from the sensor, expecting a specific range of voltages that correlate to fuel depth. When readings are out of expected parameters, it triggers the SPN 1505 fault code.
What a healthy reading looks like
Fuel level should range from 0.5V (empty) to 4.5V (full) depending on tank design and sensor type.
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 fuel level sensor wiring and connectors for damage or corrosion.
- 22. Check the fuel level sensor resistance with a multimeter; it should vary from ~0 ohms (empty) to ~100 ohms (full) based on tank level.
- 33. Ensure there's no debris or contaminants in the fuel tank affecting readings.
- 44. Verify fuel level accuracy using a known good fuel level sensor if available.
Common causes
- Faulty fuel level sensor
- Damaged wiring or connectors
- Low or contaminated fuel causing sensor malfunction
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code active?
Yes, but monitor fuel levels carefully as the gauge may not be accurate.
Will this problem come back after resets?
It can, especially if the faulty component is not replaced or fixed.
Why does this code show up with other fuel-related codes?
Fuel system components are interconnected, so faults can trigger multiple related codes.
Working a real vehicle right now?
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