I know exactly how you feel. My '93 400E doesn't have heated seats. I've been alarmed a few times by the chill, but now I expect it. However, when we went to go somewhere in her '01 ML430, she had indeed turned on the seat heat w/o my knowledge, and I was also quite surprised. She immediately noticed my reaction and informed me of it, so I didn't have to sit there and wonder why the boys were toastin'! I just turned the heater to 'low' and all was well and good. On a slight aside, during the summer I had a little issue with sticking to the leather a bit. But since I finally found some BodyGlideŽ, that's no longer an issue either.