The Peugeot 308 utilises an ‘active’ anti-lock braking system (ABS), which uses magnetic ‘poles’ built into an encoder fitted to the rear of the wheel bearing, brake drum or brake disc. The sensor has an integrated circuit, which amplifies the signal before feeding it back to the ECU. This system has the advantage that a signal (square wave) is generated regardless of whether the wheel is turning or not. This also means that the signal is far more accurate at lower wheel speeds.
The front wheel bearing on the 308 is a first generation ASB® bearing and it is therefore imperative that the bearing is fitted with the magnetic encoder facing inboard (towards the car) in order for the ABS system to function correctly. If the correct tester card is not available, a paperclip will be attracted to the magnetic encoder.
Ensure the hub and surrounding area is clean before re-fitting the new bearing and press the bearing in on the outer ring only; excessive load on the inner ring will damage the bearing’s raceways.
First Line recommends cleaning the sensor with a small amount of brake cleaner when replacing the bearing to ensure a good signal.
ASB® is now in use as original equipment on over 80% of new vehicles produced worldwide and 90% of vehicles produced in Europe. To date over 100 million ASB® bearings have now been produced.
The First Line kits for this vehicle are supplied complete with all required accessories and are part of a range which includes more than 120 ASB® bearings and this number is constantly increasing.