van overheats when running the A/C

I have a 1998 Grand Caravan. Lately, the A/C does not cool as well and the van also begins to overheat while the A/C is on. When I turn off the A/C, the van temperature goes back to normal. The van temp seems to be fine as long as I don't use the A/C. Any ideas on what could be the problem?

Thanks!

I have a 1998 Grand Caravan. Lately, the A/C does not cool as well and the van also begins to overheat while the A/C is on. When I turn off the A/C, the van temperature goes back to normal. The van temp seems to be fine as long as I don't use the A/C. Any ideas on what could be the problem?

Thanks!
When you turn the ac on check to see if the cooling fans come when the ac compressor cycles on and off , if it's hot out the fans should be on almost continuely . If not maybe the radiator fan relay has gone south .

i had the same problem , it s 90 % the relay , it cost 109 can$ , i place it mysel , it s behind the air filter , you should remove the air filter with it s box , the relay is mounted on the body with 2 screw , search on american standard product ref ry330 or with dodge reference : 4707286-6
an idea to check if the wiring are ok between this relay and the pcm (powertrain control module) when you will disconnect this relay , the pcm will register a fault code number 35 : buy haynes book for dodge caravan you will have a list of fault codes for the pcm...
hint for test temperatu sensor: also if you disonnect the cable for the sensor , the pcm will memorise a fault number 22 , means connection between sensor and pcm are good .

my question to qualified persons : why this relay got dead?
i read in hayness book there should be an optional engine block heater , between the radiator and the engine.
this piece fell down several days before my relays got dead.
i suppose that since fans are not protected from the heat of the engine , they got very hot and drow too much current then they should be , so , the relay could not support? is t possible ?
i added the photo of the relay on the members galery ...
best regards...

Had the same problem a couple of weeks ago on my 97 Voyager. It was the Radiator Cooling Fan Relay. Cost me about $60 with tax at Advance Auto Supplies here in Indiana.

On the 97 had to remove all of the air cleaner parts. It sits next to the fan. Good Luck

my 93 is having the same problem i recently replaced the A/C compressor, fan, waterpump, radiator,and thermostat im still overheating at idle with the A/C on. I have spent quite some time trobleshooting the problem and keep reaching a dead end. Im starting to wonder if its not mechanical and electrical instead. I will get to the bottom of this dilema and let you know how it goes. By the way 198,000 miles still running strong.