Wellen72

I'm trying to replace my blower motor. The Haynes manual shows a picture of a blower motor held in place by three screws. My blower motor does not have these three screws. The blower motor appears to be inside an assembly box. I'm hoping that if I can get the assembly box out of the car and open it up that the motor will pop out and I can slide the new one in but I can't figure out how to get the assembly box out of the car because it's to big and gets stuck when I try to wiggle it out from under the dash. Does anyone have any advise? It's a 2004 Impreza outback sport.