yep, I found that out my first winter. They need to be warmed up a bit before they'll turn on high, so just sit there on the cold seat, let them warm a bit with your body heat and on low. Doesn't really take that long, just needs a bit to warm up first. Just a quirk I guess. Believe there is a plug-in under the seat, so check to make sure it is tightly seated. I'd still take it in if they didn't work-why not?