Code result
P0478
Exhaust Pressure Control Valve High
Moderate severity
What it means
Exhaust pressure control valve A drive line stuck high — short to B+.
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
Short to B+
highOne of the most commonly reported causes for this code — check this first.
Related help
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