P0046: Turbocharger/Supercharger Boost Control 'A' Circuit Range/Performance

What does P0046 mean?

P0046 is a diagnostic trouble code indicating "Turbocharger/Supercharger Boost Control 'A' Circuit Range/Performance". The sensor or component is providing readings, but they fall outside the expected operating range. The part may be degraded, contaminated, or experiencing intermittent issues affecting turbo/supercharger performance.

Symptoms you may notice

• Check engine light (MIL) illuminated on dashboard
• Intermittent warning lights
• Erratic gauge readings

Common causes

• Worn or contaminated turbo/supercharger component
• Vacuum leak or intake air leak
• Clogged filter or restricted flow
• Intermittent electrical connection issue

What should you do?

This code sits in an engine peripheral, typically emissions or forced induction. It will not take braking or steering away, but it can put the car into limp mode, cost you fuel and fail a roadworthy. Book it in rather than clearing it and hoping.