Anyone know if there is a separate relay or something that controls the high blower function of a 71 with air conditioning. I opened the switch and cleaned it up but still no high. All other 3 settings working properly.

There is a separate fusible link or fuse for the high speed of the fan. The problem could be the feed to the high speed side of the fan relay, the relay itself, the fan switch or the wiring/connection from the switch to the relay. You just have to go through the process of elimination to determine where the problem is.
The first step is to see if there is 12V at the high speed side of the relay. If no, the problem is between there and the battery. If yes, see if the relay is switching when you go from the lower speeds to high speed. If yes, the problem is internal to the relay. If no, check for 12v at the coil of the relay. If yes, bad relay. If no, either a bad switch or bad connection somewhere between the switch and the relay.

Did you replace the inline fuse? Follow the large orange wire and you will find a fuse connector.

Now I'm getting somewhere. I found the large orange wire from the AC and goes around to the back near the firewall and that's it. I see the end of a fusable link on the wire but the rest of the wire is gone. Where does this wire run from there? Does it go to straight 12V?

Problem resolved. I found the air conditioning schematic and found that the high blower function runs through the horn relay but was black. I already found the orange wire with the fusable link end but did not know what to connect it to. I traced the black wire that back and the wire went over the wheel well and low and behold I found the end of a fusable link. Cleaned up the ends and put in a fuse and presto....The blower now works on high speed. Blows you to the back seat now.

Thanks for all of your help.

[This message has been edited by 71cmro (edited June 14, 2005).]

i have the same problem, but this sounds like a lot of work.

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scott--one owner '72 RS