Re: 2000 jeep i6 rad fan not turning on.
HAD THIS SAME EXACT PROBLEM...
Couple of things:
1.) replace the fan motor & the relay at the same time. IME, when the relay is fried so is the motor. The problem probably started at the motor & took out the relay. At least that is what happened in my case.
2.) Use only a Mopar relay. It will cost a little more, but worth the aggravation. I used 3 different relays that worked for about 2 months each & then would go out. since the issue was with the crappy relay, it didn't affect the fan motor.
3.) Handle this sooner than later. If left un-repaired for too long, this will start causing error codes to generate for different areas of the jeep. i.e. tranny codes, evaporation leak codes, etc. I found that as soon as I fixed this issue, all other codes ceased popping up...
4.) DO NOT use the shortcut method to replacing the relay. It did not take ll that much time to remove the front grill & headlight to access the relay location.
hope this helps...