Air Conditioner quit - PSA

Roostre · **Joined:** Sun Oct 24, 2010 3:57 pm **Posts:** 195

Just wanted to post up a quick note about our A/C quitting.

My wife told me that it wasn't getting cold when she came home from work last night. I took it out today and verified... the temp in the cab was 115 F!!! Hot, hot, hot. Checked all the fuses and the relay, but the compressor would not cycle on. There was no check engine light. I used my GDE tuner to pull the codes, but there were none. I swapped the Viscous Heater Relay into the A/C relay slot with no effect.

Hooked up a set of gauges and the high and low side both looked good. Next I pulled the A/C pressure switch connector off of the receiver/dryer canister under the coolant tank. I jumpered it and the VOILA! The compressor kicked on.

I found the local AZ had the part in stock (part # MT1911) and I was out the door for about $20. The cool thing is that this switch has a built in schrader type valve, so you won't lose any freon changing it. I had to find a very small, very short 16mm to fit the switch. Ended up using a tiny crescent wrench. I also pulled the coolant tank up and out of the way to make access a bit easier.

After I installed the switch the AC was back to blowing icy cold goodness!! :BANANA:

Just posting in case someone else runs into a similar issue and doesn't wanna shell out big bucks for a diagnosis/repair. :goink:

camo · **Posted:** Wed Jul 27, 2011 11:40 pm

nice post, thnx

Sir Sam · **Posted:** Thu Jul 28, 2011 3:54 am

Good post.

Maybe I should make a list of PSA's for the noob guide? Or maybe is it time to make the more than noob guide with things like this?

Yes the schrader valve is quite nice, makes replacement and testing of this stuff much easier.

geordi · **Posted:** Thu Jul 28, 2011 10:29 am

As an added bit of AC fun, since I *just* got my own CRD AC working again in this summer of killer heat:

If you discover that the freon has leaked out, and it seems to have leaked from the top of the compressor... Suspect the hoses. The AC pressure hoses are a pressed-together design, the manifold that bolts to the top of the compressor has a compressed connection to the aluminum hose. If the hose is capable of rotating at all while bolted down... It is bad and should be changed. It cannot be welded unfortunately, this is a bad design by Chrysler.

I replaced the high side discharge hose that connects from the compressor to the condenser for just over $100. List is $137, this hose is a dealer part only, but it comes with a new high-side sensor attached. The other hose assembly (low side orifice tube) from the condenser to the evaporator was $45 from AutoZone. Changing them is easy with the manifold design, its a 13mm nut. Just be sure to vacuum the system anytime it is opened, and the performance afterward will be MUCH improved than if you hadn't.

Roostre · **Joined:** Sun Oct 24, 2010 3:57 pm **Posts:** 195

Good to know! Thanks Geordi.

Will certainly have a look at those now.

Sir Sam · **Posted:** Thu Jul 28, 2011 7:00 pm

geordi wrote:

I replaced the high side discharge hose that connects from the compressor to the condenser for just over $100. List is $137, this hose is a dealer part only,

I had this same problem recently, I took the house down to a local AC shop who replaced the rubber hose part for $30 with new crimps and I picked it up a few hours later and installed it. Worth looking into the next time you need to replace the hose.

geordi · **Posted:** Thu Jul 28, 2011 7:41 pm

The rubber wasn't where it failed. The aluminum block that the bolt and the pipe passes through on both ends... Is NOT a single part with the hose. There is a thin circle around the underside and the top is a crimp press-fit to that manifold block. If the crimp loosens, it leaks. I don't know why the o-ring didn't keep the pressure (that is the design) even after I changed the ring twice, but there it is. The only thing that I can think of is that the pipe ripped inside the block and that is why it leaked.

Sir Sam · **Posted:** Thu Jul 28, 2011 8:41 pm

Ah, it sounded like the crimp failed and was rotating there.

Air Conditioner quit - PSA

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