Need A/C wiring help - Diesel Forum

studdy05 · 08-05-2008, 10:07 PM

Just spent $330 following the greatest single post on the Internet (this site of course) on rebuilding diesel A/C's and it worked perfectly. Thanks to all that contributed to it. Boy that air was sure cold - for all of 5 days. Today I was driving and smelled burning rubber - probably wires - and 30 seconds later my A/C went dead.

No fan blowing in the cab on any setting, either.

Can't short the dryer wires under the hood to make the clutch engage...I mean I am DOA and it's all about electricity cause I have replaced all the other stuff in the AC overhaul.

I probably blew a fuse, but I don't have a fuse diagram cause the box is lost and besides that I am more concerned about finding the short. Does anyone know what color wires to follow out or have a wire diagram?

Any ideas which end to follow first? Under the hood or in the cab?

I am game for any suggestions that might speed up the wire chase.

fjb2c · 08-06-2008, 07:05 AM

I would check your resistor. Maybe the evaporator froze and cut the air movement off so the resistor burned up along with your wires.

studdy05 · 08-07-2008, 12:12 PM

This was a rookie mistake made by me. I did what the instructions on here said not to do and added the 5th can of R134A which was causing the clutch/compressor to sieze...of course if the fuse would have blown properly it would have helped.

Instead it melted the fuse before it blew it...25 year old fuse ... they dont make them like they used to...so I scraped out the fuse, bled off the excess freon, and things are back to running correctly.

Moral to the story. 4 cans of freon - NO MORE.

Mr_Roboto · 08-08-2008, 09:10 PM

You have to WAY overfill a system before the compressor locks up.

However the compressor locking up will not blow the fuse. The compressor clutch draws a certain amount of power to close the clutch regardless of what the compressor is doing.

My guess is the fuse holder is junk, and you will need to wire in a replacement. Glass fuse holders tend to get loose and / or corrode over time. Take the 2 wires out of the back of the fuse box, and wire in a blade fuse.