Here's the dialog I had on AIM with a former BMW Tech. I just changed his name...
Tech: get in driver's seat, shut the door, and insert the key... don't start the engine... then press and hold the trip reset button on the cluster. as you hold it, it should bring up a 'service' triangle... when that happens, press and hold again.
Tech: this SHOULD (operative word) bring you into the services reset menu.... each press of the button should now change the picture on the cluster... things like an oil lamp, a picture of a radiator, the brake pad warning symbol, etc...
Tech: anything that is overdue will show red. services coming due will show yellow. services NOT due are green
Tech: when you find the 'rear brakes' symbol, press and hold again. it will come up with a 'reset?' press and hold again.... it should reset at this time.
Tech: now here's the rub
Tech: instead of resetting, occasionally it will bug. it will begin to show your brakes as 25,000 or so miles overdue.
Tech: the only fix you'll be able to do, is try to reset it a few more times. if it still doesn't work, drive around the block and try again. if it STILL doesn't go... then you must go to the dealer and they'll have to hook up
Ksfrogman: so what the dealer does is slightly different?
Tech: but they have an option you don't, by hooking up the diag tool (which has been upgraded since I left, so I don't even know what it is)