Code result
C0277
Brake Booster Vacuum Sensor Circuit Malfunction
Moderate severity
What it means
The brake control module has detected an implausible signal from the booster vacuum sensor. Loss of vacuum signal can cause hard pedal and reduced power assist.
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
Vacuum sensor failed
highOne of the most commonly reported causes for this code — check this first.
Vacuum leak in booster or hose
mediumA plausible cause — test and verify before replacing parts.
Related help
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