P01B3Alternative Fuel Tank A Level Sensor Circuit Intermittent/Erratic
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Needs a drive cycle to confirm a fix
- How the car detects it
- These codes only apply to vehicles with a gaseous alternative fuel – compressed natural gas (CNG) or LPG – as bi-fuel models alongside petrol or as dedicated gas engines; on bi-fuel vehicles a fault usually blocks gas operation and the vehicle runs on petrol. Tank level sensor A only exists where there is a real sender – typically LPG tanks with a float whose position is transmitted magnetically through the tank wall (Roush propane systems: 0.1–4.9 V). With CNG the 'level' is a calculated value. The documented systems report level faults under the petrol fuel level codes (Roush propane P0460–P0463, GM CNG van P0463), so no manufacturer document using exactly this code was found. P01B3 covers brief dropouts or jumps in the level signal – typically a loose contact or chafed wiring.
- What you may notice
- Check engine light on
- Gas level display wrong, jumping or empty
- Range or refuelling information unreliable
- Likely causes
- LikelyLoose contact or corrosion at the connector
- PossibleHarness chafed along the gas line or underbody
- PossibleSensor unstable internally
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.