Correct window heats for approx. 30 minutes then shuts its self off. this is a functio of the time delay relay under the dash. I believe switch only controls relay, switch does not stay out for 30 minutes. The knob on the switch has a bulb inside that stays lit and lights the white dot in the center of the knob when window is in the heat mode. Check the switch function with a voltmter or test light using the values in my previous post.

Rob