Draws current when turned off and loc...

Hi , this problem sounds like it could be the heater resistor, you will need to remove the right hand side trim underneath the dash where the foot pedals are , and also the side trim for the center console , you should then see a black multi plug with 5 wires that seats into the heater box , if you unplug this multi plug then check for amp draw see if you have a reading of approx 0.3 amps , the correct way to check this is close all the doors , open the boot and connect your amp tester , roll the catch on the boot and lock the car ,(with the boot still open) you will have to wait approx 16 minutes for the car to go in to sleep mode before you get a correct reading , if the amp draw is at 0.3 amps the resistor will need to be changed , the resistor is hard wired so pulling the fuse will make no difference to cutting the power . there are a few other reasons that you loose battery power but the is by far the most common ,if you need any further help you can message me at bmw_tech_38@live.co.uk regards mark