A fault code doesn’t yet mean the unit or sensor itself is faulty: often it’s the plug and connector leading to it.
Possible causes
- The unit or master cylinder was replaced but not learned
- The control unit itself
What you can do yourself
- This is an electronically controlled brake system (common on hybrids). When it fails the brakes work in backup mode: the pedal may go hard or travel further, and the stopping distance gets longer.
- If the brake pedal has become hard, soft or sinks, or the car brakes worse — don’t drive, call a tow truck.
- After the ABS unit or the sensor is replaced it has to be calibrated with a scan tool, otherwise the code won’t clear.
Stop and don’t drive on if:
- The red brake light is on, or the brake pedal feels soft or sinks
- The steering became very heavy, or the car pulls to one side when braking
The explanation comes from the error code reference in the AvtoElektrik PRO app.