Brake warning and sensor issue

[windymiller]

I recently picked up a 2007 E92 M3 with both front and rear brake warning lights on, but what appear to be brand new discs and pads fitted all round, hence taking a gamble as the price was right...

I'd assumed it may just be the wear sensors but I removed both the front ones yesterday and they appear new too - do the sensors 'wear through' or something?

Anyway, the plan was just to replace the sensors but as the ones fitted appear new I wondered if I could reset/reuse them somehow? I've tried the odometer-stalk reset procedure and it shows 'reset' but then returns the mileage to ------ and brings the warning back.

Is there a dealer reset that can be done?

As a worst case I'll just replace the wear sensors but I can't understand why perfectly good ones can't be reused - is there some kind of logic within them so the ECU knows I'm just reconnecting the old ones instead of new ones?

Clever things modern cars!

[Mvy]

Have you tried to reset the service warning from the computer? It might just be that. Check out you tube for some how to videos. Its a combo of pushing and holding the odo reset button when the car is on before you put your foot on the brake to get to the service menu.