My wife loves her BTW 320d convertible, a couple of weeks back the roof went down but would not go back up. Oh dear I thought. (Well that's the polite version) Anyhow discovered rear window regulator was at fault, the reason being water runs down the window and fills up the void just behind the door which because the drain plug is blocked with accumulated dirt and bmw cover it with a plastic underfloor cover means water can't escape. Which by the way fills up and fries the battery or sound amp, depending on which side. In my case luckily not quite but did mean the window regulator was immersed in water and gradually dusted through the site which makes the window go up and down. Hence roof would not go up because window wouldn't fully retract. So got hold of second hand rear window regulator swap them over and it all works again. So please learn this valuable lesson unless of course you wish to part with loads of money, check the drain plugs covered by plastic underfloor covering located behind the driver and passenger doors.
By
RSO ·