Code result
C0266
Active Brake Booster
Moderate severity
What it means
The brake control module has detected a fault in the active (electric or vacuum-controlled) brake booster. Active boosters are used by emergency brake assist and adaptive cruise control to autonomously build brake 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
Active booster motor or solenoid failed
highOne of the most commonly reported causes for this code — check this first.
Vacuum supply weak (vacuum pump or hose fault)
mediumA plausible cause — test and verify before replacing parts.
Wiring or connector fault
lowLess common, but worth ruling out after the more likely causes.
Related help
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