Radiator Fan: I feel like somethings missing

[Jess]

At some point, the cooling fan in my MJ died and was replaced it with one from the Pick 'N Pull that doesn't fit correctly. I've had to have my rad repaired twice over the years because of those fan strap-kits rubbing holes in the pipes. Fearing it would happen again I bought one of those later model 9 blade fans that actually fit in the slots and mount properly. I had to splice the old connector on but no big deal.

 

The thing is, I don't think I've heard the old fan run in years so I'm trying to figure out what's going on.

 

My fan connector runs directly from the fan, along the fender and firewall to the relay labeled "A/C Clutch Relay" in this picture. It's the one closest to the diagnostic ports. 

 

But apparently, there's supposed to be a temperature switch in the radiator (my rad is capped off) and a fan relay beside the airbox on the firewall? The wire itself looks factory (It's like a lighter blue wire + black wire). If it is supposed to be connected to the A/C Clutch Relay could it be not working because I have my Compressor disconnected? The A/C system isn't working so I've just had the power disconnected. 

[Ωhm]

AC is not required for Radiator Fan to work, but you do need a radiator temperature switch (closes at 190°), controlling a radiator fan relay (coil side). There is also a Fan Diode Assembly, but for now this one can wait.

[Eagle]

The temperature switch for the aux fan in the Renix 4.0L models is located about halfway down in the driver's side radiator tank.