I've been getting a "Tighten Gas Cap" error message on my TL. Apparently the best way to fix it is to order a new gas cap. You don't even have to install it, just add to cart and wait for the charge to hit your credit card! You won't see that message again!
The first time I got the message was out of the blue. I had about a quarter tank left when the information screen displayed the error.
I stopped to fill up and made sure I tightened the cap to the recommended number of clicks, plus one for good luck.
The next day the error pops up again, then again when I got home, so figure I better order myself a new cap.
It's been about five days now since I placed my order and I haven't seen the error message since. New cap should arrive today...
Makes me want a Tesla