What is happening to have the "Check AWD system" message on along with the light showing car & slippery road & check engin light on. car seems to be running just fine

Have you filled up the gas tank recently? If you left your gas cap loose and now have a evaporative emissions code I've seen on RX 350's 2010 and newer set all sort of traction control, vehicle stability control, check awd and check engine lights. Easiest way would be to take it to a dealer or a autozone and have the code pulled. If you have less than 50,000 miles it will still be under warranty and autozone will pull it for free. It really could be a number of things.

exact same thing in my car...I just got gas and just checked the gas cap and it was loose....hopefully it resets itself

I had this. The codes indicated a poor battery and one oxygen sensor. They replaced the battery and i had them do both oxygen sensors since the the car has 97k miles. But you really need to have the codes checked by someone you trust. I see postings pf people paying $3000+ to have the whole AWD module replaced, and i'd wager they are geting ripped off. Not that mine was cheap. Close to $1000, but it was with a guy i trust not to overserve me.

This just saved my bacon! I had both the check engine light and the "slippery car" indicator lit, IN ORANGE. I simply went to the tank and clicked the cap, and the lights were out! (But my left rear marker light is still out.) ha!

all your tires should be same, if not this message will come

What does that means