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A few questions...

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Old Jan 21, 2014 | 05:28 PM
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From: Fauquier County, Virginia
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Default A few questions...

Hey everyone. I just have a few quick questions.

1) It appears that my A/C compressor isn't cycling. Now, my A/C has never worked in the aspect of blowing cold air, however my compressor has always cut on when I either put the HVAC control on any of the A/C settings or on Defrost. I am getting neither, and I think since the compressor isn't engaging my stock e-fan isn't turning on either. Could this simply be a relay?

2) Where is somewhere in the engine bay I can get 12v power ONLY when the key is turned to "ON"? I need a power source for my e-fan conversion to the switch (fan has constant 12v from the battery to relay, the switch is the 12v when on only).

3) Can the little nub on the mech fan pulley be cut off? I'm talking about the little bit that sticks out past the actual mounting face. I think it is going to hit my e-fan.

4) How many amps is the stock cigarette lighter outlet? I have two 12v outlets I want to install in the ashtray and need a good 12v source to use.. and since I don't use the lighter and I think it only works when the key is on...

Thanks everyone!
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Old Jan 22, 2014 | 05:36 AM
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From: Fauquier County, Virginia
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Bump for a freezing day in VA! Lol
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Old Jan 22, 2014 | 05:45 AM
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Regarding 1): Did you check the refrig gas level?
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Old Jan 22, 2014 | 10:05 AM
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Originally Posted by Roler
Regarding 1): Did you check the refrig gas level?
No but I'm pretty sure its empty and its been empty since I bought it. However the compressor has always cycled regardless and the fan would cut on.
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Old Jan 22, 2014 | 11:55 AM
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The compressor won't run when empty. Maybe your A/C didn't work because there's a slow leak that drained you to the point where there wasn't enough juice to cool you and now there's not enough to work the compressor. There's some sort of internal switch that won't allow it to. (I think the refrigerant is also the lubricant?) I would suggest that you evacuate your A/C completely and refill. I'm guessing it'll work after that. Check for leaks.
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Old Jan 22, 2014 | 01:59 PM
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Originally Posted by Ian96XJ
The compressor won't run when empty. Maybe your A/C didn't work because there's a slow leak that drained you to the point where there wasn't enough juice to cool you and now there's not enough to work the compressor. There's some sort of internal switch that won't allow it to. (I think the refrigerant is also the lubricant?) I would suggest that you evacuate your A/C completely and refill. I'm guessing it'll work after that. Check for leaks.
Nah, the compressor is filled with oil.
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Old Jan 22, 2014 | 02:18 PM
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Oh, ok. Anyway, the compressor won't run when there's no refrigerant for some safety reason. Mine wouldn't run, I loaded it up with refrigerant, BOOM! It worked great! For 2 weeks, until the refrigerant leaked out...
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Old Jan 22, 2014 | 02:38 PM
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A convenient power-on only underhood source to switch a relay is the 12v side of the fuel pump ballast resistor. I've used this for so long on my '93 that I can't remember offhand what circuit is involved.

I guess it goes without saying that this is for a relay trigger only, not for a power source for any component.

On the '93, the fuse for the lighter is 15a in the #2 slot that also includes the radio and according to the book, a dome lamp. Not sure what dome lamp as
all interior lamps on my '93 are protected by 10a fuse #9.
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Old Jan 22, 2014 | 05:27 PM
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.

Last edited by Roler; Jan 23, 2014 at 04:15 PM. Reason: deleted due to double post
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Old Jan 22, 2014 | 05:28 PM
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Originally Posted by 1991Jeep_Man
... Now, my A/C has never worked in the aspect of blowing cold air..
Originally Posted by 1991Jeep_Man
No but I'm pretty sure its empty and its been empty since I bought it..
Really?
Mate, this is like "My car isn't running, I know the tank is empty, but can it be something else?"

May I suggest you refill it and check for leaks first.
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Old Jan 23, 2014 | 10:34 AM
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Really not a good idea to run the AC compressor without being filled plus adding the oil that is needed for the system to lubricate properly. If not working should have been disconnected.
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Old Jan 23, 2014 | 04:17 PM
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If its low on gas, the cut out switch will prevent it from working, so dont worry about that. The compressor wont engage in that case.
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Old Jan 23, 2014 | 04:51 PM
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Originally Posted by Roler
If its low on gas, the cut out switch will prevent it from working, so dont worry about that. The compressor wont engage in that case.
Thanks. I just was curious because it had ran for 4 years since I bought it when it obviously had no output cooling wise. Wasn't sure if the relay could've simply gone. I didn't use it when it didn't work... I just noted it came on with defrost. I plan to get the leaks fixed and the system flushed and refilled.

The ballast resister for the fuel pump... where is this? And yes, for the relay trigger not the actual power source. Thats constant 12v from the battery.
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Old Jan 23, 2014 | 05:07 PM
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Originally Posted by 1991Jeep_Man
Thanks. I just was curious because it had ran for 4 years since I bought it when it obviously had no output cooling wise. Wasn't sure if the relay could've simply gone. I didn't use it when it didn't work... I just noted it came on with defrost. I plan to get the leaks fixed and the system flushed and refilled.
Good man!

The ballast resister for the fuel pump...

I don't have one, but I think you can find it on the inside of the driver side fender wall in the engine bay

...
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Old Jan 23, 2014 | 08:17 PM
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Yes -- a white ceramic unit with two wires connected. On years through '94, maybe '95.
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