A couple of years ago we discovered our 98 Caravan had a slow refrigerant leak but we have been living with it. I have read that on some models, there was a known issue with the rear evaporator H valve connection. I have not checked it. I have been adding 12oz about once a year. But now after the winter has passed we noticed that we have no cold air. I cant get the system to take a charge. It looks like the low pressure switch has kicked in and therefore my compressor is not coming on. What is the trick to get the compressor to kick on when there is insufficient R134a in the system ?
Please help. This is my wifes van and when she aint happy, well you know the drill . . . . .

 

It only takes 35 psi to get the compressor to come on. Connecting a can to the system should drive you above that. The issue with the 98 caravan is the front evaperator leaking. You can fold down the glove box and remove the temp sensor grommet and look into the housing. Not to tough to tell if it's leaking. If you have a can connected and the compessor won't engage, you have other issues. You keep letting it go empty and sooner or later, the compressor will grenade.

 

Thanks for the info. This is the first time it ever went empty. I will check the evaporator as you have suggested. I am only assuming that low refigerant is the cause of the compressor not coming on. When I press the AC button, the light comes on, the engine idles up as expected, but you dont hear the AC clutch kick in. When looking at the compressor, I can see everything turning except the center shaft, which I assume is the compressor shaft. Could this problem be something dumb like a fuse ?
Also, when I connected the can of R134a to the low side, I could hear pressure. Any troubleshooting ideas you can offer would be greatly appreciated. I would like to get the AC working as we are putting the van up for sale. We replaced the tranny less than 15,000 miles ago so I want to try and get some of my "investment" back.

 

Gonna be tough for you to do at home. the control head asks the pcm to turn on the a/c, it looks at all the sensors and decides weather to or not. It could be a fuse. It is fuse 11 in the fuse box under the hood.