My heater won't turn on in my 2000 Grand Prix, what could it be?
How did it fail? Did you slowly lose fan speeds starting with low speed and ending with high speed? If that's the case its the resistor in the heater duct. (You tube it for location and how to change it). If it blows but just isn't hot, check your coolant level. If its low you won't have heat. If its full then it could also be the actuator in the duct work which directs the air through the heater core. Do some careful trouble shooting before you start spending money on the wrong parts, or hours taking things apart. Hope this helps.