Hello all.....This is my son's 79 Berlinetta 350 4 bbl that we are restoring while he drives it. Our project of the week is getting heat into the cabin as well as defrosting. When the cooling system was refurbished a new radiator and heater core were installed by a local mechanic. The air temperature that does come from the vents responds to the temp control lever so I assume that the heater core is OK. Please correct me if I'm wrong. Having said all that, the problem is the fan doesn't blow. I've done a little research and without looking recently at the car ( it's his daily driver) I want to know the most effecient way to track down the problem. I do know its not a fuse so I am guessing the culprit could be a relay, blower motor, etc. I need info on where these dang things are located and try to fix this without tearing it up. Any help is appreciated. Thank You

 

I don't think there's a relay on it, but the blower motor is mounted right under the dash on the heater box. If you look under the dash you will find it, and then you can pull the power lead off the motor and test for voltage with a meter with the fan switch on. If it has power, then pull the motor and try running it while out by putting a 12 volt lead to the motor, and ground the housing.
Also check to see if the temperature controls actually function when moved. Could be a cable is broken, or off the arm that it operates, which will mean the fan could be running, but the "door" not open to allow air flow.

 

Thanks for your help. I was able to take a look under the dash today and boy, what a mess! Vacuum lines rotten and missing, broken wires, unplugged componets, etc. Does anyone know how to obtain a drawing that explains the routing of all that stuff? Haynes manual is no help.

 

Yes, you can get reproductions of original shop manuals for about $21. They show diagrams for all the wiring and hoses for the entire car. Eckler's has them here:

http://www.ecklerscamaro.com/product...&dept%5Fid=226

 

Thank you!

 

Problem solved! When the new heater core was installed, the guy neglected to connect the wires to the blower motor. Just in time, it's getting cold! BTW, this one does have a relay and the blower motor is on the firewall, upper passenger side. A real PIA to get to. Have to drop the fender well. Thanks for the help!

 

Yes they are a PITA! I replaced mine once, and it's due for another when it returns from the body shop and paint.
I modified my heater box while I had the front clip off, and made it two piece, so from now on it will be a snap to replace the heater core!