06 LJ A/C issues after blowing ice cold for years

[Johnnyswell]

Hey all, looking to get some help at diagnosing why my A/C stopped blowing cold air last week mid-vacation.

I had it inspected 3 weeks ago in PA and the mechanic has tossed a new serpentine belt on it along with new spark plugs and new brakes and rotors as it needed these no doubt. 2006 LJR just hit about 104k on the odom and she's very well taken care of. I've never had an issue up until last week when I was driving around in the rain in southern NJ on vacation when I pulled in to a beer store to grab a 12 pack with the A/C blowing cold. Rain started to pour down by the time I went in the store and came out. I ran to the Jeep, started it, threw it into reverse, backed out of the parking spot, threw it into 1st gear quickly, heard a little clunk, and drove out of the parking lot. IDK if the clunk is related but I thought I might add it in there incase something happened to the compressor during that clunk. A/C has been not working what so ever since then.

Things to note/what I've tried:
- Checked and swapped fuses in glove box and in fuse box under hood
- No rattling from compressor clutch
- Compressor seems to want to engage
- Hooked up one of those cans with R134a to see if charge was low but compression seemed good on the reading (I still tried to add some though but not much because the gauge was in the red meaning it's probably not a charge issue)

Is there a world where the new serpentine belt could've caused this wear on my compressor?

What should I try next or look for?

Thanks in advance, I'm still on vacation and praying it's a quick fix or solution. See's suspiciously odd that compressor would go 3 weeks after inspection...

 

[g.hayduke]

I once had my evaporator ice up in the rain and stopped blowing cold. I kept the fan on but AC off till it melted the ice and started working again

 

[Johnnyswell]

I once had my evaporator ice up in the rain and stopped blowing cold. I kept the fan on but AC off till it melted the ice and started working again

Appreciate the input. This was last Thursday and super humid in the pouring rain. Would've thawed by now no? I was just outside fussing with it and had it idle for a good time on different a/c settings. No luck.

 

[DuckNut]

First thing to check is if the clutch engages when the AC is turned on.

 

[Johnnyswell]

First thing to check is if the clutch engages when the AC is turned on.

It wants to, I can hear it trying but nothing really happening

 

[DuckNut]

It wants to, I can hear it trying but nothing really happening

There is no - wants to. It either engages or not. If it engages the face plate spins. If it engages and doesn't spin it is seized and going to destroy your serpentine belt. If it does not engage, the face plate does not spin.

If it is not engaging force it to by jumping the low pressure switch.

If it then engages you have low refrigerant or a bad low pressure switch.

You cannot trust the gauge on the bottle.

Here is my guess...the valve stem started leaking after the shop did their inspection. What I would do...hook up a can of refrigerant and give it a little charge and see if it kicks on. If it does you have a leak.

 

[g.hayduke]

I also had the high pressure Schrader start leaking after hooking up gauges. In the end, my evaporator was leaking.

I found both problems after buying a black light flashlight and injecting some dye.

 

[Johnnyswell]

There is no - wants to. It either engages or not. If it engages the face plate spins. If it engages and doesn't spin it is seized and going to destroy your serpentine belt. If it does not engage, the face plate does not spin.

If it is not engaging force it to by jumping the low pressure switch.

If it then engages you have low refrigerant or a bad low pressure switch.

You cannot trust the gauge on the bottle.

Here is my guess...the valve stem started leaking after the shop did their inspection. What I would do...hook up a can of refrigerant and give it a little charge and see if it kicks on. If it does you have a leak.

Okay, so the clutch definitely spins freely on the serpentine belt so it engages.

I tried adding a little bit from a refrigerant can from an auto parts store and still nothing. Didn't want to add too much and cause other problems as it was already showing it in the red.

Where would the valve stem be leaking at and where is that in our systems. I'm a rookie with this stuff.

Appreciate your input.

 

[DuckNut]

Okay, so the clutch definitely spins freely on the serpentine belt so it engages.

Let's clarify.

Turn the engine off and look at the compressor,..you will see bolt heads.

Start the engine and turn on the AC and look at the compressor. Do you still see the bolt heads as they were when the engine is off?

 

[Johnnyswell]

Let's clarify.

Turn the engine off and look at the compressor,..you will see bolt heads.

Start the engine and turn on the AC and look at the compressor. Do you still see the bolt heads as they were when the engine is off?

Yes the bolt heads are in the same position.

How can I go about jumping the low pressure gauge?

 

[DuckNut]

Yes the bolt heads are in the same position.

Your compressor is not engaging. They should be spinning so fast you cannot make them out. Just a circular blur.

You now have a choice.

Take it back to the shop that worked on it or start down the road to repair yourself.

If you choose to do it yourself you are going to have to have a vacuum pump and ac gauges.

Since I have all this equipment I would do it myself. Since you don't, take it back to the shop or take it to another.

Where would the valve stem be leaking at and where is that in our systems.

There are two of them. The low side (the one you hooked your can to) and the high side, it is on the smaller metal hose and looks exactly like the low side, except a little smaller.

 

[Johnnyswell]

Your compressor is not engaging. They should be spinning so fast you cannot make them out. Just a circular blur.

You now have a choice.

Take it back to the shop that worked on it or start down the road to repair yourself.

If you choose to do it yourself you are going to have to have a vacuum pump and ac gauges.

Since I have all this equipment I would do it myself. Since you don't, take it back to the shop or take it to another.




There are two of them. The low side (the one you hooked your can to) and the high side, it is on the smaller metal hose and looks exactly like the low side, except a little smaller.

Okay, I appreciate your insight here. Thank you sir.

 

[CharlesHS]

IF the gauge is in the red your system pressures are equalized between Low side and Hi side meaning the compressor is not spinning.
IF the compressor were spinning the gauge would read in the green or blue indicating good charge, low charge or really low charge.

 

[DuckNut]

IF the gauge is in the red your system pressures are equalized between Low side and Hi side meaning the compressor is not spinning

Good call.

 

[txbemis69]

unplug the low pressure switch and bridge the plug attached to the wires with a paperclip. does compressor kick on? if yes, go get a new low pressure switch and replace old with new. if compressor doesn’t kick on you have a problem with the compressor or low refrigerant. my low pressure switch died and i had no cold air. i bridged plug and compressor kicked on so i replaced low pressure switch and all is well.

 

[KennethS]

unplug the low pressure switch and bridge the plug attached to the wires with a paperclip. does compressor kick on? if yes, go get a new low pressure switch and replace old with new. if compressor doesn’t kick on you have a problem with the compressor or low refrigerant.

I think you have sone conflicting information there. Jumpering the low pressure switch will cause the compressor to turn on if the switch is bad or if the refrigerant charge is low. More investigation would be needed to determine which it is.

 

[tr21triton]

I think you have sone conflicting information there. Jumpering the low pressure switch will cause the compressor to turn on if the switch is bad or if the refrigerant charge is low. More investigation would be needed to determine which it is.

He said he added some freon to it, but I didn't think it would take it if the compressor isn't cutting on.

 

[CharlesHS]

Depending upon what the outside air temperature was at the time; equalized system pressure should have been >90 psi.
The OP said he tried to add a little refrigerant with the gauge in the red.
Doubtful he added any refrigerant with the system pressure that high unless he heated the can (not recommended).
While the clutch may move slightly; I doubt the compressor is spinning.

 

[LJBean]

Interesting thread. Great information and observations. I'm getting ready to completely replace my AC system because it doesn't seem to be working like it should - probably because I fell for the leak stop snake oil in the past. So instead of replacing one piece at a time, I'm gonna do it all. I need to replace my heater core anyway, so while in there, I figured I'd replace the evaporator as well - then, following the Jeep owner's creed, I decided to replace the next part and the next part. Next thing I knew, I've assembled the whole AC plumbing system.

 

[KennethS]

He said he added some freon to it, but I didn't think it would take it if the compressor isn't cutting on.

That is correct. My point was jumpering the low pressure switch would (should) cause the compressor to turn on if the switch were bad or if the refrigerant charge were low.