A/C Diagnosis...

[Steven Walker]

Hey all!

First post ever and I've searched all over this forum and didn't find anything and Google is about as good as a warm beer. Anyway my issue on my 93 f-350 is the a/c system. I have nothing, no power to the switches (I checked every wire that connects to that entire panel). I checked for power at the blower motor and all that jazz and still nothing. I checked the main fuse panel under the dash and no blown fuses and nothing looks to be cut. My question is: Do the switches supply the power to the other components? Or does the power go to a hidden relay somewhere and could that be the problem? I've been fighting this SOB for the past month and still haven't been able to figure it out.

Any help, advice, or ideas are greatly appreciated!

 

[79jasper]

Have you looked at a wiring diagram?
Ignition switch *cough*cough*

Sent from my SM-N960U using Tapatalk

 

[Steven Walker]

I haven't been able to locate any wiring diagrams. I've been looking for them as we speak. As far as I know the ignition switch has been functioning fine, haven't had any issues with it yet but I'll give it a gander. Thanks

 

[IDIBRONCO]

I've seen some key switches (where you actually insert the key) get some wear in them. They'll let you start the engine, the engine will keep running, but nothing inside is turned "on". Sometimes, the alternator won't charge. If this happens, all you have to do is turn the key slightly toward the "start" position. It's worth checking out.

 

[Steven Walker]

I replaced the switch and now it wont start with the key... so I'm thinking the cylinder is bad??

 

[franklin2]

It started before you replaced the switch correct? Sorry to say it, but it's probably something you just did since it started beforehand.

Your new ignition switch (the one mounted on top of the column behind the dash) came with a setup pin didn't it? And instructions? They told you to insert the pin and have the keyswitch on the column in a certain position, and then tighten it down? And then pull the pin? And that sets the position of the new switch? At least that is what I remember from when I changed it on a 80 ish model.

 

[Steven Walker]

No it didnt come with a pin or instructions but I was finally able to get it working. But that wasn't the initial problem apparently because I just replaced the blower motor and now I have air movement but the ac clutch isnt engaging... I haven't found anything on diagnosing these things yet... any tips?

 

[IDIBRONCO]

You can pull the plug off of the low pressure switch and jumper across the two wires in the plug. If the clutch engages, you're low on freon. If you are, don't run it for too long. Compressor damage can occur if it's very low.