Brake Pad Wear Indicators
Pad wear indicators have evolved from the standard metal clip or audible sensor to the electronic wear sensor. They both warn the driver when the brake pads require replacement.
Metal audible clips are in use on many late model vehicles today. Sometimes the clip has to be removed and placed onto the new brake pad before installation. These clips come into contact with the brake rotor when the pad wears down to a certain thickness. This contact produces a squeal warning the driver that the brake system requires attention.
Electronic sensors provide a warning light for the driver. This is a less intrusive way of indicating pad wear to the driver. When this wired circuit is interrupted the pad wear warning light will activate on the instrument panel. The down side to all this is by the time the drivers light comes on, the sensor's circuit has already been broken requiring sensor replacement. These sensors can be tested for resistance with an ohmmeter.