I just purchased a 2000 grand cherokee with a 4.0 motor and 137,000 miles. The temperature gage seems to reach 210 really quick. Coming home today it seemed to be running hot in traffic with the a/c on. I have read several posts and can someone please clarify something. The electric fan was not running with the ac on. Should it turn on immediatley when the a/c is engaged? I have seem post state it does not come on immediately the temperature has to reach 218. It did not overheat, but i dont want to risk it, i have slow commute with alot of time in traffic. Is there a fuse for the electric fan? All if have right now is the owners manual, and i dont see a fuse for the fan. Any suggestions on what i can check or how i can check to see if the electric fan is functional. I also have a 1990 and it does not run hot, even with the closed systems. Any help would be appreciated. Thanks

 

There is a 40 amp fuse in the PDC under the hood by the battery. The fan is controlled by a "pulse modulated" relay located underneath the passenger's headlight, but you have to cut a hole to access it or remove the entire headlight mounting bracket. The relay is controlled by the PCM which sends a signal to the relay, depending on conditions. Here's how to access it;

The relay is only $6 at the wrecking yard or $36 from rockauto.com

 

As a followup to my last post; I just did mine and after removing the headlight, I found the PO had already cut the hole! Easy-Peasy, 15 minutes, done!