Electrical Control Problem
 

Electrical Control Problem
My 05 X3 had no electrical problems until about a month ago. Then the battery drained (dealer traced the drain to sunroof control module so he unplugged it-no drain now . Since this happened I did replace the battery because of age and winter coming. Since this issue started I have had intermittent working Radio(displays station but no sound and clock display);center console controls(seat heater,etc); Instrument cluster turn indicators but outside turn indicators work; servotronic steering assist ; instrument luster lights come on after 1-5 minutes ( with headlamp switch on). The next time I start the engine everything may work but if I shut the ignition off when everything is working and then re-start the engine all the things listed don't work again . It seems that now if i leave it overnight the next morning everything will work but this is not always so. I have checke the system with an Ammeter and the system goes into "sleep" mode after about 15 -20 minutes. after researching I replaced the ignition switch and the headlamp switch and this seems to have helped with the frequency of not working on start-up but not corrected it.
My local dealer is very busy and seems to be not so interested in helping me resolve this issue and electrical gremlins can be very challenging .
I am hoping someone here may have had similar issues and can offer directions.
I have checked the exposed grounds and all are ok and there is no interior water damage,etc.
Thanks
Wayne

It might be a K-bus problem. Maybe this page can help you www.bmwgm5.com/k-bus_troubleshooting.htm