P004A

Turbocharger/Supercharger Boost Control B Circuit/Open

P004A is a generic OBD-II powertrain diagnostic trouble code: Turbocharger/Supercharger Boost Control B Circuit/Open. It is logged by the engine control unit when the turbo/boost monitor detects that a specific fault threshold has been exceeded — typically resulting in the malfunction-indicator lamp (MIL / check-engine light) being illuminated.

Code

P004A

Group

Powertrain

System

Turbo/Boost

Severity

Warning (MIL on)

Need P004A disabled?

RaceTune permanently disables any OBD-II trouble code on supported ECUs — for motorsport, off-road, and export use.

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Detailed reference content for P004A is being prepared. What you see above — the code's group, system, and the software disable option below — is accurate and complete; the long-form explainer, common causes, symptoms, and diagnostic steps will appear here once they have been reviewed.

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Disabling P004A in software

RaceTune can permanently disable P004A — and any other OBD-II diagnostic trouble code — on every ECU family we support. The monitor is disabled inside the ECU itself, so the fault stops being logged: the warning light stays off and the engine never enters limp mode for this code. The change is tied to your exact software version.

Permanent

The monitor is disabled in the ECU itself — not just cleared. It cannot return.

Tailored to your file

Each patch is matched to your specific software version — never a one-size-fits-all file.

Reversible

The original file is always preserved. Reflash the stock to return the ECU to factory state.

Software modifications affect emissions compliance and are not road-legal in many jurisdictions. RaceTune service files are intended for motorsport, off-road, and export use.

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