best thing to do is take your car back to a local scion dealer. free for the check because still covered.

 

best thing to do is find a parking structure or somewhere where there's no snow/ice and run around in there and brake a lot. if it still happens, then take it to the dealer. if not, then it's the abs and the whole snow/ice thing. don't buy new rotors/brakes or anything.

 

this happened to me once. what happened was a walmart receipt slipped under one of my pads.

 

going to dealer is the best option i guess