I live in Central Florida. Some days you run the AC and some you run the heat. I had the AC on auto and turned the heat up all the way. Heat was coming out of driver vents but passenger side was Ice cold no heat at all. I turned on the passenger side and turned the dial all the way up still no heat on that side. My car is 1999 STS with all the options. Thanks for the help. Gregg

 

u need a mode door actulator passenger side
door not moving

 

Thanks for the info. I'll need to check out the cost of this.

 

Same thing happened to my 2000. Bought one on ebay for around $95. Took about 1/2 hour to change. Good luck