Code result
C004C
Brake Booster Motor A Position Sensor Exceeded Learning Limit
Moderate severity
What it means
Brake booster motor A position sensor learned offset exceeded the allowed range. Boost control tracks commanded vs. actual manifold pressure; persistent deviation means wastegate, vanes, hose or actuator are not delivering the requested pressure.
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
Calibration not performed after replacement
highOne of the most commonly reported causes for this code — check this first.
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