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 hydraulic unit (ABS unit) or electric brake booster
- Air in the brake system
- Low brake fluid level
- Low voltage: a flat battery or corroded terminals
What you can do yourself
- Stop in a safe place and test the brake pedal: if it’s soft, sinks or the car brakes worse than usual, don’t drive on — call a tow truck.
- Check the brake fluid level in the reservoir and look for fluid traces at the wheels and under the car.
- The brake system needs a scan-tool diagnosis and a check for air in the brakes.
OOleg’s tip: check the connector
Often the cause is simple — there is no contact in the connector (plug). Look at the connector from the back: remove the rubber seal and you will see whether a wire is corroded or has come off completely. Corrosion shows up as green deposits. Ideally, gently pull each wire towards you one at a time: a sound wire stays in place, while a corroded one simply comes off — it needs to be repaired.
Unplug and inspect connectors with the ignition off.
The explanation comes from the error code reference in the AvtoElektrik PRO app.