What would cause a 2002 Mazda Protege 5 to have no heat?

Answer 1

My 2002 Protege5 did the same thing. It happened after i had some audio equipment installed. When they pull your radio out there is a cable to the left that as you turn your nob to hot and cold u will see it move. If there is any kind of weight on the cable then it wont open and close the flap for the cold and hot. I am going home and double checking mine today! I pulled my head unit out this weekend and i needed my heat and it happened again. Its a real easy fix you can def dyi. You jsut need the keys to pull ur head unit out i got mine at Walmart and you need two sets there the Ford keys.in the shape of a U and you use two in each side. the center hole will have the over lappin keys it is supose to be like that. then put a little outward pressure on the keeys once clicked in and your unit will slide out. hope this helps!