Re: Rear Spoiler
I read you post closely and saw you said you have already replaced your battery.
I did replaced mine years ago as well and was sure I had tightened the terminal clamps tightly.
I then was having intermittent electrical issues and months later I grabbed the terminals and gave them a twist and sure as hell
the positive clamp turned and therefore it was NOT tightened securely.
I removed the terminals and tried a trick told to me by a mechanic I know.
I replaced the terminals and before tightening them down I stuck the wire of a paper clip between the post and the clamp to help ensure that once tightened it was really tight.
This trick solved my intermittent problems and I was amazed that a slightly loose battery terminal clamp could cause the issues I had.
By the way the wing coming up was one of my issues and went away.
Good luck....these cars a complex when the power is interrupted in any way