y is my fan not working?!

The fan doesn't come on until the engine reaches around 240 degrees...it's a stupid design. I'd recommend getting an aftermarket fan controller and hooking it up to the factory fan.

On a four cyl Mustang, the fan is controlled by a CCRM or IRCM, a box of electronics.

On my 89, it is the CCRM and is under the dash to the left of the steering wheel, and on the 93's, I think it is on the pass side inner fender under the hood.

Failure of the wire connections to the box is rampant. All of the fan power comes into the box, through the relays and back out. So any poor connections will overheat the wires and melt the plastic of the box, making the connection worse.

There are aftermarket wirepigtail kits, as well as Ford kits to repair the wires.

I ended up fixing mine twice, then just using the CCRM to control some relays that power the fan. Its worked for 3 years now.

you could use a switch thats inside the cabin of the car...only thing is that you may forget to turn it on...I'd just use a lighted LED switch so I would remember...unless you wanted to do it properly then you will probably wanna use the normal CCRM or whatever controls the fan