New Owner, New Problems

Hey everyone, I am new to the jeep world and having a few issues with my recently purchased 99 cherokee sport. 189k miles. 4.0. auto. 4x4.

first thing I noticed my A/C compressor wasnt coming on with the HVAC switch so while trying to figure out why it wasnt working I gained a CEL.. Once I got my hands on an OBDII scanner it came back with "P0443" which is the evap purge solenoid. Which Ive scavenged a few at the local yards and none of them seem to make the slightest difference.

So after I racked my brain and searched everywhere for probable causes I've gained a seccond code for a fan circuit...

So pretty much as of right now Im looking at an EVAP leak that I have no idea where else to check, A/C compressor and secondary fans not working.. Any ideas on where to begin looking would be a major plus.:cheers:

Thanks in advance - Kyle

If the compressor is not running I'd be willing to bet the system is low on refrigerant. If you unhook the low pressure switch on the top of the receiver/dryer and jumper the connector that should make the compressor clutch cycle with the power on.

As for the P0443 You also should be looking for a vaccum leak. If the evap system doesn't get or hold vaccum it can set a code. I've run across more than one XJ that the connector on the side of the intake manifold is brittle and either fell of or doesn't seal correctly. You can use something like carb cleaner to spray around the hoses and fittings to look for leaks. If you spray one and the idle speed changes you have a leak.

I usually try to not use something flammable to do this but work with what you have.

Thanks for the reply. I'll try jumping it today. And as of right now plugging and unplugging the switch on the receiver/dryer raises idle as it should. If that makes any difference in the equation..

Wheeling365 has great advice. I used the Carb cleaner method on a friends to find a vacuum leak. Cold engine is a suggestion.

The increase in idle is a good sign; up until that point the electronics are good, now hopefully the compressor will engage when you jump the wires.

Btw, I see you're in sc, where did you get your Jeep?

~posted on my DROID X2

I bought it off of a guy near Charlotte, Nc

So...... The switch on the receiver/dryer must work because I pulled the connector and jumped those 2 wires and the idle raised as it should but the compressor nor the fans came on as they should.. Sometime today Im going to have the A/C checked and see if it is just low on freon.. But I still dont understand what the deal with the compressor is.. I dislike things that work intermittently and leave a bright ass orange light to shine in my face... PITA

Let me know if anyone has had this happen before lol back to the drawing board it is...

On my 99, after sitting unused for some time, the compressor clutch just got rusty. For a while it misbehaved and ran for a while before it quit, making me think it was a refrigerant problem when it wasn't. Eventually it quit altogether, and I "restored" it by throwing some oil at it and giving it a few judicious whacks with a hammer. Careful, though, because it's easy to bend things.

Check for power at the clutch connection on the compressor when you turn on the AC. If it's getting 12 volts but not engaging, it's the clutch. If it's not getting the 12 volts, it's somewhere else.

. . . So after tinkering around tonight my buddy figured out a way to check the evap solonoide... The voltage on the meter is the pink and black wire on the solonoide... And that was the voltage reading... I've read it should be a lot higher like in the 10v range. As you see it's not.. As soon as we connected a 12v lead to the solonoide the a/c compressor kicked on and so did my aux fans... Going to the parts yard tomorrow to see if I can scavenge a PCM.. As long as the part numbers are the same and it's a 99 it should be compatible right? Thanks again -Kyle. Sorry if the pictures are huge or crappy.. Stuck using an iPhone.