Blower Fan Problems 97 BLazer

My Daughters 97 Blazer's fan motor seems to have a mind of it's own. There are times that the fan does not want to run at all and other times is will run fine. There are times when it will run fine in the 3 lower speeds but will not run in high. I have never been impressed with the volume of air it moves even on high but especially on the lower settings.
Does anyone know what the aprox. voltages are for each of the 4 speeds? couldn't find that anywhere called a Dealer and no answer either.


I have checked for voltage at the blower motor but with the terminal unplugged I seem to have varying voltages depending on the speed selected. I read a post here that said I should have back probed it with the motor drawing current to see if there was voltage or not. Anyway I am thinking that the resistor and switch are okay? If the current is getting to the motor. I have not checked resistance on the ground wire to the motor. but I will

When I fooled with it the other day it seemed like the connection/connector at the motor was the problem and when I pushed on it to the left it would run on high and to the right it would quit...cleaned it up as best I could bent the terminals a little tighter..but she told me she still had some problems with it after my "miracle cure"

I am assuming that it's the motor and have purchased a new motor, and will install it....I'm just wondering if there is anything else I should look at first...

I printed a few answers to posts on blower problems from "Old Master" and will attempt to following his trouble shooting advice. Any guidance appreciated.


Spit

Mybe this will help someone else...seems like there are more than a few posts on blower problems. I found a couple of bad terminals in a wiring connector right next to the connector for the blower motor. It's sort of a barrel shaped connector... an inch or so around about 2 1/2 or 3 inches tall and it's right in front of the blower and right behind the ECU.

Anyway there's 4 or 5 light gauge wires in this block and 2 10 or 12 guage wires. The terminals for for the heavy wires one red one black, had gotten loose overheated and started to melt the bakalite barrel. My guess is that when it ran on high the current draw through the loose connection heated the one of the terminals up enough to break the connection. I took those 2 wires out of the multi wire connector and hooked them up with individual butt connectors. seems to have done the trick.

Spit