Heater/AC Fan

[huladick]

Recently bought a 1980 and I'm having trouble with the fan. No fan in any position. Replaced the fuse and looked at the switch assy. All seems OK. Any relays or anything else to check ? Thanks.

 

[Bob Chadwick]

Get yourself a test light and see if you have power coming into the switch. If so, is there power coming out?

Bob

 

[jetech]

Hi Huladick
My 77 has the same problem. I jumpered the motor with 12v from the purple wire at the fan resistor terminal located in the plenum downstream of the fan and found the fan is ok. I then jumped 12v to the relay located near the fan resistors and found that it works but the controling circuit for the relay coil is dead. When I get time I am going to trace the circuit from the fuse block to the fan switch and see if I can locate the problem. There is also a by-pass circuit that powers the fan at low speed always. This by-pass circuit has a fuse that is shown to be located by the master cylinder but I can't find it. I am not sure the 80 is the same but I don't see it being much different. Look for an electrical troubleshooting and schematic manual. I got mine on Ebay and it is 77 specific. If you need more info let me know. It seems like half of the electrical circuits on my car don't work.

 

[huladick]

It sounds like this is a common problem for these year models. I spoke with an experienced mechanic and he said he has changed many of the controllers. Wouldn't surprise me to find the same. Thanks for your help. Dick