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 valve inside the brake unit
- The ABS unit connector: corrosion, water
- The ABS unit’s fuse or power supply
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.
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
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.