I have a 2002 Blazer, built in NJ USA, but bought 2nd hand from Japan, and to make things more confusing, I live in Zambia. My problem is that when I switch on the Aircon, or heater, nothing happens, until (and this is the strange part) I either switch on the Winshield wipers, or the headlights. I only have to switch either unit on, and off straight away, and the Fan starts working. I am no mechanic, and no electrician, so am just looking for suggestions that I can give to the garage. Any suggestions appreciated