Originally Posted by omodos

BMWX5CHI hi
the light normally goes off after about 16mins, BUT have read it does not for everyone, only way to see if you have a drain is pull out spare and get to battery and wire up a digital voltmeter in the circuit (use a screwdriver to get hatch lock closed so the lights go out too, and just close all doors no need to lock) and wait 16-17mins you should see the amp draw drop on the meter to sub 0.05amps after this time........there are loads of sites on the web with pics on setting up the multimeter....officially the drain for an e53 shuold be max 40ma....but thinking of it now if you have a drain slighlty above this e.g 50ma and happen to purchase a replacement battery with a higher capacity than the OEM this must be a good thing as you are counteracting the slightly higher drain with a bigger battery (anyone out there please feel free to correct me)