My electric fan only comes on when AC turned on. What could be at fault? Can I run a splice into a wire and hook a toggle up to it? And if so how?

 

That's the only time its supposed to come on? That's the only time mine used to come on.

 

My engine overheats when im sitting still at light and with weather getting warmer its been hitting over 230. It cools off once I start moving again or turn air on

 

Sounds like the fan clutch needs replacing.

 

Should come on with ac and when temps hit 218. You can wire in a switch to control it. Search on here for write up.

 

Its not a fault. That is how is is set up from factory. It will also kick on if you run defrost. Yes you can hook a toggle up.


It is common search for overheating at idle. There could be alot of different reason for it to over heat. Extremely common issue on here.

That is one possibility. Could be as simple as a radiator flush.

X2

 

Fan clutch and get a lower thermo switch, u can also go big n go with big elec fans, pull the thermostat as well!

 

x2 on the thermostat. I just unplug the temp gage wire when I go wheeling and the fan will stay on. it helps to plug it back in and check if you get to a stopping point on the trail but you can usually feel the engine knock when she reaches the 260 degree mark. it will also turn on your engine light but it will go out within the next day after plugging it back in.

 

thermostat is a low temp, fan clutch is mopar and been replaced twice since i bought it in 2010, coolant might need to be flushed just a pain to do it.

 

Eh, it's not too bad. Can definitely get pretty messy. But with summer here, it's a good idea to do take care of that now

 

the thermo switch has been replaced also beginning of the year. is there a relay or a way to check the auziliary fan to make sure its supposed to come on at certain temps?

 

Are you talking about a coolant flush?

 

I'm rebuilding the '96 XJ SE that I got (for free) a couple months ago. It came to me in pieces. It has the 4.0, and I can't keep the temp down. I am running two 12" electric fans(on switches),new thermostat,temp sending unit and temp switch. Sitting at idle the temp runs up to almost 260,and even running both fans won't bring it back down. This is my first Cherokee,so I am looking for some advice.

 

Coolant flush is wise for summer. Does the fan have a relay and how can I test the fan for whats wrong with it? works with ac but not with temp

 

If all the cooling components have been replaced and its still runnin above 220 at the hottest point then its goin to b a head gasket! Takes about 2 hours!