I have a 2001 330xi with the premium and cold weather options. However, there seems to be a couple of options that are either missing or turned off. First, the rain sensing wipers. I (thought I) following the owner's manual on how to turn on the rain sensing wipers but they don't seem to work. How exactly can I check to make sure they're on? Is there some way to disable them which means I would have to re-enable them somehow? Second, the headlight washers. How can I tell if they're installed and working? BMW also has on file that a previous owner repaired the parking sensor but I can't tell if it's installed. I don't hear anything when I back up.