P2BB2

Alternative Fuel Tank Empty

Moderate severity

The AFCM detects that the alternative fuel tank is empty. Bi-fuel vehicles may switch to gasoline operation; mono-fuel vehicles cannot continue without refuel.

Common causes

Tank actually empty - refuel required
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $20-220
Level sensor reads empty incorrectly
A plausible cause — test and verify before replacing parts.
medium
Typical part cost: $20-220
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First things to check

1Confirm the code with a scan tool and check for additional related codes.
2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.

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Related codes

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Frequently asked questions

What does P2BB2 mean?

P2BB2 means "Alternative Fuel Tank Empty". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.

What are the most common causes of P2BB2?

tank actually empty - refuel required; level sensor reads empty incorrectly — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.

Can I keep driving with this code?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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