2004 nissan qust heat and radio stoped working
Take it to the dealer. These have some strange electrical dependencies between the heating and cooling systems, and other electronics. I had a nuisance problem in my Mercury Villager that began with the A/C going out. (The Villager and Quest were assembled on the same assembly lines by Ford). There was a knock on effect on other parts of the electrical system. So my advice is let the experts figure it out.
Search Nissan Quest Questions
Nissan Quest Experts