Originally Posted by Dundas
My May 08 build E92 is due for routine service which the dealer tells me includes a software update. Can I leave the new controller in or do I need to put the original controller back in for the software update?
Based on what reading I've had in the various forums the general concensus seem to be to put the orignal back. Unless you have an awesome realtionship with the dealer. With the original in place the update should go without a hitch. If there are problems with the update and you leave the newer controller in they may "blame" it on the controller. Easy enough to change out after. Also, according to those in the know as long as the software ver is E89x-09-06-510 or greater the new controller should work.
Hope it helps.