2005 dodge caravan cooling fan works fine with A/C but wont work automatically to cool the engine

Thanks for choosing FixYa and welcome. The fans are automatically shut on when the a/c is turned on in this van. This is normal. If they are not kicking on properly, there is a bad wire. You need to check the wires, visually, and see if you see any damage Christy. It would appear burnt wires or black marks on the wire. Make sure none is torn or ripped in half. Be careful around the fans though. You really need a voltage meter to test the current in all the wires. If they come on with the a/c, then the fans are ok. Check your fan fuses also, just in case. If you are experiencing overheating, there are several things that can cause this. Make sure coolant levels are correct. Make sure the cap is on tight, as well as all hoses. The most common cause is the thermostat, followed by the water pump, valve, or impeller. A bad head gasket can cause overheating also. You may have a bad coolant sensor. If you have a check engine light on, take it to Autozone or Advanced and have it scanned. The light comes on when the computer detects a problem with the vehicle. If so, it may have detected yours. Hope this helps. Best regards Christy. Ricky.

Check cooling fan relay and fuse.

? the cooling fan inside the vehicle isnt the same fan that cools the radiator. The AC runs off a compressor pump and the blower motor(fan) distributes it through the vehicle, the blower motor also distributes the heat from the heater core when its set on that. If your motor is overheating and the cooling fan isnt starting the fan itself may be defective or the thermostat that controls it.