OBD-II code · Chassis
C0571 Active Brake Assist Performance
The brake assist or driver assistance module has detected that brake assist performance is degraded. The system may fail to autonomously build pressure during emergency braking and emergency brake assist functions are limited.
Is it safe to drive with C0571?
Usually safe for short trips, but don’t ignore it: the underlying fault can get more expensive over time.
Common causes
- Most likelyActive booster slow or weak
- PossibleSecondary fault on related sensor
- Less likelySystem calibration required after repair
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
Repair at a glance
- Difficulty
- Hard
- DIY friendly
- Best left to a mechanic
- Typical labour
- 1–5 h
- Emissions test
- Usually unaffected
- Parts involved
- Active Brake Booster, Brake Assist Module, Brake Pressure Sensor
Related codes
Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.