AC Issues! help?

05ram4x4 · Jul 2, 2014

Lately it's been around 90 degrees, and driving my truck just sucks. My ac does not work at all. And, I don't understand why! I did a vacuum test on it, and it showed no signs of leaks. I tried adding freon, and almost immediately, the low pressure side was too much. Compressor clutch never kicks in. And it seems to stop accepting freon. Any idea? I really need to get this fixed.

dodge dude94 · Jul 2, 2014

Sounds like the low side pressure switch could possibly be out.

05ram4x4 · Jul 2, 2014

Is there any way to test that?

dodge dude94 · Jul 2, 2014

Might have to check in the 01 FSM.

05ram4x4 · Jul 2, 2014

Alright, I found it in the FSM. I always forget I have that saved! But Ill try to test it soon.

dodge dude94 · Jul 2, 2014

Good deal, man. Remember to report back with your findings.

05ram4x4 · Jul 2, 2014

If I put a jumper in the plug for the low pressure switch, shouldn't the compressor clutch kick on?

05ram4x4 · Jul 3, 2014

I tried testing the switches. I don't seem to get anything out of them, whatever I do. Could the pcm be bad?

Sometimes it will work (kinda). For example, this morning the ac was on. (About 75 degrees out if that makes a difference) The compressor was kicking on and off about every second. I assume that's just low freon. But maybe after 10 minutes or so, it just stops doing anything.

That was at about 6:30 this morning.

Now it's about 4:30, and I start up my truck after sitting all day and it does the same thing. Kicks on and off, but stops maybe 10 minutes later.

I've read that the pcm controls the ac system. Any ideas? I'm just lost now...

dodge dude94 · Jul 3, 2014

I would take it to the shop and have them jumper the switch and check the pressures. It's behaving as if the refrigerant level is too low.

05ram4x4 · Jul 3, 2014

Well I can jump the switch and check the pressures. Last time I checked them they seemed correct. Jumping the switch doesn't do anything though.

05ram4x4 · Jul 10, 2014

Alright, I'm almost 100% I fixed it. I jumped the coil to the battery and it didn't do anything. I grabbed done from the junk yard, that seemed to work, and put it in. Now it seems to work fine. I was charging it up, and put a whole 20 oz. can i think. Now the clutch is always engaged. Is that right?

dodge dude94 · Jul 10, 2014

As long as the pressures are okay and it's blowing cold you're good. It's summer, it won't cycle all the time.

05ram4x4 · Jul 11, 2014

Thanks. Everything seems to work fine now! Im so glad I have cold air again!

MoparMagic'00 · Jul 12, 2014

05ram4x4 said:
I jumped the coil to the battery and it didn't do anything.

care to explain what you mean by jumping to coil to the batt? Kinda lost me on that...

05ram4x4 · Jul 12, 2014

I took some wire I had sitting around and jumped the two terminals on the battery to the two connections at the coil. So, it had the 12 volts it needed.

MoparMagic'00 · Jul 12, 2014

05ram4x4 said:
I took some wire I had sitting around and jumped the two terminals on the battery to the two connections at the coil. So, it had the 12 volts it needed.

you referring to the clutch on the compressor? sorry im still learning my hvac stuff

05ram4x4 · Jul 12, 2014

Yes, the coil is an electromagnet that pulls the clutch in.

05ram4x4 · Jul 15, 2014

Alright guys, help me out with this. IN the morning, m ac works fine. For about 20 minutes or so. But, only if i use it constantly. Then it becomes warm ad the clutch disengages. It doesn't disengage unless I give it some time.

Another example, which might be easier to explain, is on my way home from work. I start up the truck, crank the ac (max a/c, full fan speed) and it's nice and cold. Stays cold, clutch stays on, or cycles, depending on the temp outside. Then, maybe 20 minutes later ( a/c running constant the whole time) the clutch disengages and it gets warm. It doesn't reengage or get cold unless i give it 10 or so minutes. Why?

I tried searching about this issue, and people have mentioned the expansion valve freezing up, and blocking flow. Then after it thaws, it works again. But our truck don't have expansion valves, do they? Just orifice tubes?

Any ideas?

MoparMagic'00 · Jul 16, 2014

just the orifice if im not mistaken.. it also may be freezing up... or the coil may be getting too hot and disengaging.. it makes sense to me that its gettin too hot and letting loose

05ram4x4 · Jul 16, 2014

What would fix that?

AC Issues! help?

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