OBD-II code · Chassis

C0634 Brake Pressure Sensor A/B Correlation

Brake pressure sensors A and B disagree beyond plausible deviation.

Is it safe to drive with C0634?

The car may go into limp mode (reduced power). Get it diagnosed before a long trip.

Common causes

  • Most likelyOne sensor drifted

Symptoms

  • ABS warning light on
  • ESC/stability control deactivated
  • Possible reduced brake assist
  • Speedometer may behave erratically

Repair at a glance

Difficulty
Medium
DIY friendly
Best left to a mechanic
Typical labour
1–4 h
Emissions test
Usually unaffected
After the fix
A drive cycle is needed before the light stays off
Parts involved
Brake Pressure Sensor A, Brake Pressure Sensor B

Code data: OBDex open dataset (CC0). Labour times are typical ranges, not a quote.