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Discussion Starter #1
So I replaced my ac compressor and to my horror it would not turn on. I'm an Elect. Engineer by degree so I could easily track it Down to the 12v supply to the relay being burned out somehow. The compressor woks and the ac fuse is in tact. The relay woks as well when I swapped it with the horn relay and tested it there.

Any ideas if there is another fuse to look at other than the 10amp one under the glove box?
 

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other than the a/c relay switch? I can't think of anything.
There is the main fuse block, which goes two ways, one to ignition switch, the other to the a/c relay (which I'm not 100% positive where that is located). And after ignition switch it goes through the PJB (under glove box) fuse, and through the a/c relay as well, and then all lines lead to the unit itself

This is likely a very dumb question but (you know what they say about questions).. was it plugged in?

Actually.. you know, there is a thermal protector at the end of the line before the ground; could that be.. dead?
 

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Discussion Starter #3 (Edited)
I am confused by the thermal protector you are talking about but I have it working with some work arounds.

So initially I thought the compressor was not fully plugged in so I jacked the car up, removed the splash guards, front passgenger wheel etc to get at the plug (and its still hard since its so short on the compressor side). All I think I did was mess things up as the connector came off the wire from the compressor. I was able to finally get that fixed and it still did not work.

I turned on the AC and pulled and reseated the relay and could hear it clicking on. So I checked the voltages to the relay and one of the same relay type (the horn) to see where the enable and where the 12V supply came in. Well on the relay the enable worked (turning the relay on) but the supply was dead. I then checked the AC 10A fuse and it was good (checked with a $200+ Fluke Multi-meter) and also tried swapping a 25A fuse for the heck of it (even though I knew it wouldn't work).

Still no 12V to the relay supply line. I decided to manually connect power to the relay supply since I can't explain where its burned out and why it didn't take the fuse out like it should have. So I pulled up the engine side fuse box as much as I could but it was a rats nest nightmare under there and I didn't want to try and rewire anything under there at all.

So what I did was take the supply relay connector prong, bent it up 180 degrees around the body of the relay so the prong wouldn't go in to its normal connector when I reseated it. Instead, I soldered a wire to it that would come up and out. I then connected that wire to a fuse then to the battery directly. So now my relay has fused power connected to it (like it should have had something not burned out). Now it works great, air is colder than ever. It turns on and off like it should, I just have an extra wire but I did a good job with proper connectors and heat shrink and everything so its not too bad.

Its still frustrating that the relay supply burned out with no fuse at all that I could find burned out. I checked every last fuse I could find, took them all out to look at. Then to top things off I took out the +12V horn supply too when in amperage mode on my multi meter, I was testing the horn and connected the horn relay supply line to the compressor. I guess the compressor drew too much current but again there was NO fuse bad. What the hell? So now I have two relay mods, one for the horn and one for the AC compressor.

At least I have cold air finally. Last week sucked without it with me driving 70 miles a day or more to work. As much of a nighmare this compressor swap ended up being (and costing $600 with the vacuum pump, test gauges, connectors, R134 etc). it still is better than the bare minimum $1200 it would have cost elsewhere.
 

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a/c problems have been popping up everywhere for everyone; then again I guess it's a season thing lol, just makes sense.

Your issue though is very strange. I hate to say I'm glad you found a solution but.. being a "wrong" solution.. is a bit worrisome.
 

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Discussion Starter #5
a/c problems have been popping up everywhere for everyone; then again I guess it's a season thing lol, just makes sense.

Your issue though is very strange. I hate to say I'm glad you found a solution but.. being a "wrong" solution.. is a bit worrisome.
I'm trained in electronics so I know its not going o cause me any problems, its actually a more reliable wiring job than what was there before due to its simplicity but this kind of thing should not be required. The fuse under the glove box should have blown. The fact that it did not is worrisome for the sake of this car's reliability going forward and for others as well.
 

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I'm trained in electronics so I know its not going o cause me any problems, its actually a more reliable wiring job than what was there before due to its simplicity but this kind of thing should not be required. The fuse under the glove box should have blown. The fact that it did not is worrisome for the sake of this car's reliability going forward and for others as well.
The fact that this is such a unique problem should be encouraging though. It's the first I've ever heard in a 3, and I've never run up against a similar problem in any car I've owned. Luck of the draw it seams.
 

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So I replaced my ac compressor and to my horror it would not turn on. I'm an Elect. Engineer by degree so I could easily track it Down to the 12v supply to the relay being burned out somehow. The compressor woks and the ac fuse is in tact. The relay woks as well when I swapped it with the horn relay and tested it there.

Any ideas if there is another fuse to look at other than the 10amp one under the glove box?
10 amp in the engine compartment for ac/clutch.
 
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