P02CB

Turbocharger/Supercharger B Underboost Condition

Moderate severity

Boost pressure on the secondary turbocharger/supercharger (B) is below the lower threshold. Wastegate stuck open, charge-air leak, or VGT vanes stuck open.

Common causes

Wastegate stuck open
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $170-2750
Charge-air pipe leak
A plausible cause — test and verify before replacing parts.
medium
Typical part cost: $170-2750
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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 P02CB mean?

P02CB means "Turbocharger/Supercharger B Underboost Condition". It is a generic OBD-II code that points to a fault in the fuel & air metering (injector circuit).

What are the most common causes of P02CB?

wastegate stuck open; charge-air pipe leak — 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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