reelthing

help. Since I was redoing my interior, I decided to try and put in a new fan switch for the AC/ blower in the console. It did not solve the problem, the system still behaves the same as the old switch. The blower motor only comes on when the switch is in the highest detent. Does not operate in the other three positions. What about the blower resistors? I saw them for a 78-82 in ecklers. Where are they located on a 82? Any other ideas or troubleshooting?
UPDATE: I finally replaced the resistors, but that did not work either. The only other item is the Hi Blow relay? What else could it be?

markdtn

High speed only is usually the relay.

C3 4ME

Yeah, but I thought the hi speed relay if it wasn't working would mean it would work in all positions but high, which is opposite of what we have here.

SIXFOOTER

The Relay and the Resistors are right next to each other on the firewall. The relay picks up with the switch in HI and powers the blower right off of the fuse links below the white connector at the back of the pass side valve cover.
In this pic you can see the relay, mine is painted gold, just to the right of the hood latch


This schematic has some notes on it that will help you understand whats going on.

Get a test light or a volt meter and leave the resistor plugged in. Put the black lead on the voltmeter on an engine ground. Put the red one in the connector on the blue wire. There should be some voltage there with the key on and the selector on Low. Next position and the reading will go up, next position and it should go up again.
If it does not, check the Tan, Brown and lt blue wires that feed the resistors from the selector switch.
I am asuming you checked the 25 amp AC Fuse, if not, go there first.

PS, make sure the ground wire from the blower motor is connected to the ground stud at the corner of the AC box and that there is a ground strap from the stud to the engine

7T1vette

Replace the fuse in the fuse block. The low speeds use that fuse; the HI speed uses a 30a. fuse on the left inner fender well [in front of master cylinder].

markdtn

Not in my experience. I have seen a lot of these relays fail just like this one.

reelthing

Ok, sixfooter: Here are the results; I get 11.45v, 11.70v, 11.89v when I probe the dk blue wire still attached to High speed Blower relay and run the switch thru its range. I get 11.56v at the orange only when I should at high switch position. Funny thing happened when I pushed on the high speed blower relay connector. The fan speeds worked on all speed momentarily. I tried to repeat by taking off the relay and cleaning connectors but it returned to the state it was in.. only operates on high. It has got to be this relay..right?

81_vette!

I replaced the Resistor, the Relay and the interior Fan Control Switch. I have checked my wiring to the proper diagrams and still I only get high fan speed. Fuses look good as well. I can live with the fan speed on high only... as that's the way I would run it most of the time... but what a PITA this little issue has been. I even put on a new Blower Motor, and it really works well on high speed!

It's got to be something simple... looking me right in the face.