Code result
P004A
Turbocharger/Supercharger Boost Control B Circuit/Open
High severity
What it means
Open circuit at boost control solenoid B (twin-turbo or two-stage system). Same diagnosis as P0045 on actuator B.
Is it safe to drive?
No — stop driving
This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly.
Most likely causes
Wiring break
highOne of the most commonly reported causes for this code — check this first.
Pin pushed back out of connector body
lowLess common, but worth ruling out after the more likely causes.
Cracked solder joint inside the module or sensor
lowLess common, but worth ruling out after the more likely causes.
Related help
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