Code result

P02CB

Turbocharger/Supercharger B Underboost Condition

Moderate severity

What it means

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

Is it safe to drive?

Use caution

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.

Most likely causes

  • Wastegate stuck open

    high

    One of the most commonly reported causes for this code — check this first.

  • Charge-air pipe leak

    medium

    A plausible cause — test and verify before replacing parts.

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