The wear indicator is a control device that signals when the brake friction material has reached the minimum thickness or wear threshold. For disc brake pads, the thickness is typically two millimeters.

The wear indicator can be acoustic or electronic.
The acoustic wear indicator is a hook-shaped element installed on the backing plate of the brake friction material. It acts mechanically by rubbing. When the friction material reaches the wear threshold, during braking the hook comes into contact with the rotating braking disc, causing a squealing noise.

The electronic wear indicator consists of a wear detector integrated into the brake friction material, an integrated circuit connected to a warning light on the dashboard. When the friction material reaches the wear threshold, the signal contact is interrupted, the electrical circuit is closed, thus turning on the indicator. Depending on the type of braking system, 2 or 4 signal contacts can be installed.

Wear indicators are made of materials that offer high resistance to corrosion, high temperatures, aging, and UV rays, ensuring maximum reliability and durability over time.

Alltech S.r.l. supplies all-cable ECE-R90 certified brake pad and shoe wear indicators to leading global industrial vehicle manufacturers.

Added to these is Pads – Control, the brake pad wear indicator for trailers and semi-trailers. The system signals brake pad wear before it has irreparably damaged the brake discs, or worse still, the brake calipers. Via a light signal, the system provides a warning signal in good time when it is time to replace the brake pads. The system is quick to install, requires no mechanical work and adapts perfectly to the various types of existing axles.