Posted this in the ome section and no one responded, so I figured I would put it over here. I have a 88 XJ 4.0 auto with the factory tow package. I must put in a new radiator, hoses and thermostat and I noticed when my ac is on my electric fan lang coming on. So my question is what and how to I test the system to check if the fan is shot?

 

The e fan comes on when the AC is on or get temp gets up too hot...

 

It should come on instantly when the a/c setting is on, unless your low on freon. Disconnect the fan, hook up a test light to the plug and turn the a/c on. The light should light up instantly.
It could also be a relay on its way out.