The headlight wiper motor on my 2002 S60 has recently started running continuously, making an annoying high humming noise as soon as I turn the key. I'd like to disconnect it, but don't know how to do this. Can anyone help me with this?

The battery in our 2002 S60 went dead, so car has no power. However, we hear a small whirring, high pitched whiny noise coming from the area of the Fuse panel inside the car- Any ideas??? We are replacing the battery, but has anyone heard of this? I am almost afraid to attach the new battery.....