On some 2007 3 Series BMWs (E90, E91, E92 & E93), the CBS system may indicate the brake pads are worn out when in fact they are not.
The problem is a software glitch that overestimates the amount of brake pad wear.
BMW tech bulletin SI B 32 02 08 (April 2008) covers how to use a factory scan tool to check the CBS
estimated brake wear by comparing calculated wear against actual wear.
If the two donΆt match, the fix is to reprogram the Dynamic Stability Control Module with updated software from BMW.
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