element is broken. someone's fat ass has been ploppin in a little too hard.you can buy a plug and play replacement from a used Volvo parts bin for about $65, but then you have to install it, which involves removing the seat, then the back from the bottom, then the leather cover.
I found a heated seat for sale on the bay once and got the seller to pull the element for me, and sold it to me for $30 bucks. I then got my drivers seat redyed and conditioned at my boat upholstery shop, and put the new element in all for about $90. I reinstalled the seat, plugged it back in, good as new.
Now I need to do the passenger seat, but if I do, my lab will have to ride in the back...or get a cover for him.