I'm having some issues with my 13 over heating. I put 12v to the large prong and the little prong and grounded the black wire coming from the fan assembly. It did absolutely nothing so thinking i did something wrong and hoping it's not the TIPM
I took it to a local mechanic and he confirmed it was a bad fan. Come today I get the new fan assembly, plug it in and start the Jeep and it starts to overheat and the fan doesn't run. Im hoping someone can help me diagnose this.

 

I've had the exact same issue (cannot jumper the fan to life), and have been hesitant to buy a fan because the TIPM signal has also been undetectable via multimeter (though I can't be sure I'm doing it right) -- did you come up with a resolution?