I have an 82 Elky and my friend has a 78.

The blower fan suddenly quit working on his 78 and I am trying to help him figure out the fix but not having any luck, so I need your help.

Here's what I've tried so far without any results.

Checked fuse--good
Changed relay from my 82 Elky which I know is good. No help.
Changed resister from my 82 to his. No help
Bought a NEW fan switch and installed. No help.
Checked all connections and wiring for corrosion and fraying. Found none.
Checked fan motor by wiring staight to battery. It worked fine.
Checked ground wire from motor. Its good.

One thing I have noticed though. When I turn my vacuum selector switch to the desired positionm air/ heater/defrost/ etc. I always hear a click coming from under the hood and I don't hear that on his.

Could the vacuum selector switch be bad and keep the fan from working?

OH yeah, I checked the red wire that runs from fuse box to relay and it has power but the purple wire that runs from the relay to the blower motor won't light up my test light. Also, my test light won't light up at the four prong connector that goes to the fan switch either.

I'm stumped! Anyone got any ideas what the problem could be?
Thanks in advance for any help and sorry for the long post.

Follow the brown wire about 8 inches from the blower switch connector back towards the fuse panel. You will find inline a black plastic connector. Usually this connection will be burned and losing connection. The connector burns due to an old blower motor drawing too much current through the circuit.

PS, the relay controls the high blower speed only. I thought I wrote an article about this already...lemme check.

Ah, found it...it's the "No high blower" problem, but, it has wiring diagrams!
Lookie here (http://elcaminocentral.com/showthread.php?p=179171)

Follow the brown wire about 8 inches from the blower switch connector back towards the fuse panel. You will find inline a black plastic connector. Usually this connection will be burned and losing connection. The connector burns due to an old blower motor drawing too much current through the circuit.

:-D Yep! That was the problem! I had even looked at this connection once and it appeared to be fine. It didn't look corroded or anything so I left it alone but after reading your post, I decided to check it out again and scrape and clean it real good and it WORKED!

Man, I really appreciate your help. I worked for approx. 3 hours trying to figure out the problem with no results. I should have asked here first I guess. Thanks again Acauth1.

Thanks for the info. The brown wire was spliced at some point but don't remember seeing the black connector. I will do more checking.

there is a brown wire accessable from the ac vent and or glove box

Ain't this place great!!! You struggle, you trace everything, you do all you can to find the problem with no luck, then you make a simple post and (presto up pops the answer)
El Camino Central Rocks!!!!:You_Rock:
Donny

Yeah, I guess. Even if this thread is, six years old.

8 years later its still helping people out. Thanks, this saved me a lot of time.

It just goes to show ya that the electrons still follow the same path 8 years later.....:smileyb:

Good info regardless of how old it is :beer:

Sometimes they do just that.