Can you get a very small bladed screw driver behind the switch to pop it out. Once you get it out I guess you would jsut have to figure out someway to open up the switch so as to get to the lamp. I am guessing it is in the center console or on the dash somewhere. Most of those switches are jsut pushed in and held by tension withthte plastic clips on teh switch housing itself. I am jsut guessing at most of this but maybe it will point you in the right direction. We didnt have heated seats on any of the cars I worked on when I was a Toyota tech.