I just installed a new heater control and attached all of the plugs (the control and to the blower). The fuse was blown immediately. I haven't taken the time to trace wires yet so I was wondering if anyone has a good starting point for me to look at.

OHM it out for shorts first. Then trace back to see if wires are routed as intended with all insulation intact where it goes through fire wall. Also a good idea to verify fan turns freely by hand, as a locked rotor will draw infinite amount of current in a DC application.

Big Dave

I haven't dug into this very much. Is there supposed to be a wire running along the firewall the goes to the blower motor? If so, mine doesn't have a wire and I haven't looked into the fenderwell to see if there is a motor there at all. What is the muti-wire plug for that goes on top of the heater box on the inside of the car?

i don't know if this would be of assistance or not... here's a link for the wiring schematics for '62 through '79 ChevyII/Novas... click on appropriate year, click to enlarge to full size then right click-save to your files ;)

http://rides.webshots.com/album/555104780qhTHfK

I dug around the wiring today and found that the orange blower motor wire was cut and taped off in the engine bay. I then spliced a section of wire to it and attached it to the blower motor. After putting another fuse into the panel for the heater, it blows immediately after turing the key to the "on" position. I guess I will need to pull the blower motor out when I get around to body work and paint.

The multi plug is for the speed resistor. Unplug it there and try another fuse. Is this a factory AC car?

No A/C.

Once again do you have a multi-meter? Electricity is invisible and really, really fast so you are going to have to read a meter to test the circuit. It is the only way of finding the problem.

Big Dave

Yep, I have a multimeter but I haven't had a lot of time to really dig into the wiring.

Did the fuse blow after unplugging the resisitor? and the reason I asked about AC is there is another circuit on AC cars for the high speed blower.