Quote:
Originally Posted by Godders
It uses the measurement and the known travel for each rotation of the stepper motor in the caliper. Every few hundred miles once you stop, exit and lock the car, provided you've left the handbrake off (level surface and in Park) the caliper will cycle the pad in a nd out to check the remaining pad material.
Excerpt taken from an Audi SSP (translated from German so doesn't read too well) :
"Brake pad wear detection and correction clearance
The pad thickness is cycled (every 500 km) when the vehicle is stationary and parking brake is not actuated. It is designed to automatically cycle the brake pad from the zero position (= position in final position) against the brake disc down. The control unit determines from the Hall sensor the measured value from running the brake lining and it can calculate the pad thickness. The measurement takes place when the vehicle is parked, Ignition switch and parking brake is not closed. If a driver uses the parking brake regularly, the wear measurement may be less accurate than for rarely used Parking brake."
So if you're leaving your car on a level surface leave the handbrake off occasionally.
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It's snippets like that that are gold dust! We had a thread on weird cycling of the parking brake a while ago and nobody came up with a proper explanation. Thanks Godders
2nd February 2012, 11:56 AM
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