2000 Town and Country Rear A/C not cooling

One condensor, 2 evaporators, one in the rear and one in the front. If you had to add freon to the system at one time, theres a leak somewhere and that could be in the front or rear a/c. You could have someone add dye to the system and use a black lite to locate the leak, if i had to guess I would say it is in the evaporator...the front one. But if the system is low on charge now it will not be very cold out of the vents.

Glenn Beasley Chrysler Tech

The front air remains cold.

I also forgot to mention.. When the front air wasn't very cold, i heard a sound like air slowly evacuating (or entering) a cylinder. That's the point where I first took it in and they added Freon.

That same sound is now in the rear instead of the front. And its loudest in the trunk area where the air return vent is. I'm guessing the rear evaporator must be in close proximity.

Does that change your diagnosis any?

No. Keep in mind if the system is low on charge, the front can still be cold because the distance from the compressor is closer to the front evaporator then the rear. The hissing noise you heard from the front was a low charge. The rear has an expansion valve which could cause a problem but is very rare, I have never seen a faulty one yet on that model. There is also a blend air door that switches the door from heat to a/c in the rear box, that could cause a problem if the door was out of position or the mode actuator is bad but is also rare. The test you did with the buttons on the control panel that I posted on here before does not do anything for the rear heater or a/c, there are no self diagnostics test for the rear. And the fact that you said you had a leak before and never mentioned that a leak was repaired tells me you still have a leak and the proper fix is to recover/weigh/recharge with dye and leak test. My opinion only Glenn Beasley Chrysler Tech

Not sure I mentioned a leak, rather just water condensation dripping to the ground.

Guess I'll take it to the dealer. I have a decent after-market warranty that should cover it if something is at fault.

Thanks for the advice.

You mentioned them having to add refrigerant. Refrigerant doesn't get used up, it is either full or it leaked out. Do you have any specialty A/C shops in your area? The dual a/c systems aren't all the uncommon but they are rare enough that your average joe mechanic might not have a whole lot of experience iwth them. Maybe you have a thermo-king in your area? They only do A/C and mostly do big things like the coolers for the refrigerated haulers.

I'm not sure if they changed the design since 93, but on my 93 Dodger Grand Caravan, every few years I have to get the metal gasket where the hose from the front to the rear connect at the H-valve replaced. In the Midwest, the salt used in the winter corrodes the gasket and is a common source of leaks. (also was told that the r134a reacts with the metal gasket and breaks down, that's why they came out with a upgraded, telfon coated gasket) But when this happens to me, I loose both the front and rear A/C, so it may not be your problem.