I was changing the fan speed on my '79 wagon today after changing out the a/c compressor. Blowing ice cold now, but then when I changed fan speed the fan conked out on me!!!! It did this once before and then came back. Now I don't have any fan speed at all, when I turn the a/c on the compressor doesn't kick on. Fuse is OK. I think maybe the connector behind the a/c control unit???

Anyone know about these?

Dan

 

I posted the problem about the fan and a/c not working. I pulled the control unit out and found there were no loose connections. Are there any relays that run both the fan and a/c clutch? Or is the fan speed resistor linked to the compressor that if it conks out the clutch won't engage either???

Any help would be great!
Dan

 

I think you are on the right track. It sounds like your HVAC control isn't getting any power. I had a similar problem in mine. The single power connector to the HVAC control unit had melted. Easy to overlook because it looked fine on the outside. It's a large plastic connector on mine. Not sure how it looks on yours. I wouldn't be surprised if it's the same as it is a "Packard" style connector. I discovered it had melted when I went to probe it for power. I replaced the connector and haven't had any problems since. I have no idea what caused it. I replaced the blower as a precaution. It could have been drawing too much current due to age. That's the only cause I could think of. Make sure you are getting power to the control head before you do anything else. Keep us posted!

 

Thanks for the heads up! I will put a probe and see what I get. The fuse is ok, which if something melted and shorted something out it should have blown the fuse. Anyway I will check there first as it's easy. then I will locate the relay for high blower speed and check if it's good also.

Thanks again!
Dan

 

EXCELLENT!!!!!!!!!!! I found the brown wire on it's own, I first checked for power at the fan switch and control unit. NOTHING. I then found the brown wire and there was no power at first but after scratching around in the plastic holder I did get the power, hooked it up and YES! The fan came on again. Now I have to find out how to get at the wire to replace the connector as it's embedded deep in the cavity where the control unit sits. any ideas? Do I get at it from under the dash on the driver side? Then I can get to the end of it and put in a new connector

Thanks!!!!!!!

Dan

 

Sorry I didn't get back to you sooner! You will have to be creative to get to the wire. I remember it was tricky getting to the connector. I don't know what the guts of your dash look like. Remove whatever you can around it. I recall removing (or at least unbolting) the control head. Glad to hear you found the culprit!