Spoiler warning light
 

I have a minor annoying issue with the spoiler warning light coming on. I have researched this a fair amount but can not seem to get to the bottom of it. It comes on randomly. While it is on I can manually operate the spoiler without problem. If I turn the car off light goes off.
I have taken relays out and cleaned, checked fuse, cleaned the switch under dashboard.
Any suggestions where to go next.
Speed sensor issue?
Micro switch in the trunk?
Thanks much