Code result

P04A1

Exhaust Pressure Control Valve B Low

Moderate severity

What it means

Same as P049F with the control line shorted to ground.

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

  • Control line shorted to ground

    high

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

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