I would imagine they are somehow connected. I also saw strange things happening when I didn't have the switch on correctly. One would fold, then when I pressed the button a second time the other would fold, then another press and one would fold out followed immediately by the other one.

I kept fussing with the switch assembly and looking at the one that I removed (I replaced it with one from eBay). Once I got it in the right spot everything synced up and worked perfectly.

Now, as an earlier poster stated, if I can just keep my passengers from slamming these doors!!! They'll shut THEMSELVES if you just stay out of their way.