Hi, new to the forum. I've just bought a '98 E200. The only issues I have are that the sunroof and boot release don't work. There sounds like there's power going to the motor of both as there is a slight 'whine' when I press the button. Also the sunroof makes clicking noises. I've tried the crank that was supplied to open manually and reset and it seems to be stuck. Any ideas? Someone mentioned it may be a vacuum pump. I have no clue what that is!