My fan only blows air on the highest setting. The air cools great, but I would really like to be able to use it on the lower three settings as well. Some people keep telling me that this is likely a relay switch thats gone bad. My question is now, how do I know for sure and how do I fix it? I would really like to not take it in to someone to fix, especially since I am on a post full of mechanics.
I'd check the resistor pack. Except for high speed, all the other speeds send the power thru the resistor pack. It should be located on the side of the ductwork somewhere with four or so wires plugged into it.
Well, we'd first need to know which "flavour" of climate control system you have.... would this be the manual climate control set up or perhaps the dual range electronic climate control?
I am totally ignorant as to what a "post full of mechanics" is but I imagine a military base where a lot of guys have tools..... Sadly, owning tools doesn't assure knowledge - especially when we are discussing what might be a pretty sophisticated system.
This can be complex... For these types of concerns (and I have been doing this stuff for enough years that the military will NOT want me hanging around waiting for my heart attack) I refer to the workshop manuals and the wiring diagrams. I identify the system I am working on and I proceed with a logical diagnostic progression.... Knowing "for sure" is going to entail some "testing" using "tools".....
Flesh out your post with some pertinent data, let us know if you have a DMM and give us some idea of your abilities.... If it was as simple as you seem to think, I'd be out of a job.....
MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.