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 brake booster assists weakly, so the driver presses harder than usual
- The pressure or pedal position sensor reads wrongly
What you can do yourself
- If the brake pedal has become hard, soft or sinks, or the car brakes worse — don’t drive, call a tow truck.
- This is an electric brake booster (fitted to hybrids, EVs and some newer cars). If it stops assisting, the pedal goes hard: you’ll have to press much harder and the stopping distance gets longer.
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.