No climate control

KingCarGuyZ

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Alright guys, I’m a little stumped, yesterday, after a short trip up to school the Jeeps climate control decided to take a hike. Had the A/C running the whole way up, but after sitting for about 2 hours, it was broken for the trip back and has stayed broken since.

so to classify broken: no blower motor on any setting, fan or position selector. A/C compressor does not engage in any setting (used to see it spinning when the engine was on, now no matter where you put the positional selector the compressor won’t engage) I think I can still hear the vacuum assisted doors closing and opening when I move the position switch, but it’s hard to tell.

background: been fighting this A/C system for a while, it has a small leak that I am idly looking for (mostly just feeding it Freon every 4-5 months) I just replaced the fan speed switch about a month ago with a duralast untit (not OE, but it was available) When I replaced the fan speed switch the compressor would engage but the blower wouldn’t run. When it needs Freon A: the A/C sucks. And B: the compressor is either off or cycles quickly, while the blower functions normally.

what I have done so far: checked all of the highlighted fuses/ relays by swapping them into known functioning systems and testing (broke the green HVAC one testing it, electrically it’s fine, but I plan to get a new one shortly)
6FC8D318-0087-40EE-9812-AD129CF74A81.jpeg

Checked the blower motor resistor, looks normal.
9DA19DB0-6613-4C4C-9E9B-702ECF39E870.jpeg
17B559B2-183C-4C1A-B3C5-61764EA07871.jpeg
532DD26A-7C65-46F0-AA19-23C4D81359F7.jpeg

also went ahead and replaced the 10amp HVAC fuse behind the glove box, though it tested ok.

blower motor Dosent run when heat is on either

cleared the computer for giggles (didint really think it would work but mind as well try)

any ideas? I’ve got a trip coming up this weekend and I would really Like A/C
 
Before you go crazy try applying 12v to the fan motor directly from the battery, beyond that I would suspect the Duralast fan switch.
 
Before you go crazy try applying 12v to the fan motor directly from the battery, beyond that I would suspect the Duralast fan switch.
I was suspicious of the fan switch to, but how does that explain the compressor not engaging? 12V at the motor is a good idea, that connection is below the battery correct?
 
So I need to pull the battery and try that, but I found some interesting things nosing around with the volt meter.
The 10amp fuse behind the dash has 12V
The green 40amp fuse under the hood has 10V (seems fine to me)
The 10amp relay under the hood has less than 1V. This I find concerning
DD1C8251-0B75-47F9-AB26-7E005BFC3FCE.jpeg
591D979A-4CAF-483D-9749-2BDD851235D2.jpeg

These tests where all Co. ducted with the panel in the following set:
62AF267F-2A89-4011-9306-0DDCCBCC994A.jpeg

If you adjust the middle knob, the motor pictures below spins (seems normal)
320CF40A-E333-4141-A8E4-B9CF36F153FA.jpeg

(Passenger footwell near the top left of the passengers left foot)
 
Found it, loose connection at the blower switch, don’t know why that made the compressor not work. But I have A/C now.

edit: after putting the dash back together I know have a Jeep that has a working blower motor, but won’t crank at all🤦‍♂️
 
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Well it has been a long F-ing day.

Somewhere while fixing the blower motor, I broke the ignition switch actuator, I have run, acc and off so that’s a small blessing. But not start, jumped the relay and got her moved to an ok spot. Picked up parts about 1/2 an hour ago (ignition switch actuator and ignition switch) and hopefully will finish installing tomorrow. Just once it would be nice for her to stay completely fixed for like idk, a whole month.
 
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Glad you figured it all out.

The signal for AC comes from the switch panel. (Note that the HVAC switches are on the ground side of the circuit). So if you had a loose main ground to the switch panel (I'm guessing the loose connection was the 3 wire connector), no signal was being sent to the PCM (by way of the low and high pressure switches) to tell the compressor to engage.
 
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