Is there a way to test the fan clutch?
I bought my cherokee a month ago and found out that they jumpered the electric fan, everything seems to be ok, but I would like to fix the basic/stock issues before doing anything else.
What other reasons could made the previous owner jumper the electric fan?

Thanks

 

Maybe a bad coolant temp sensor? A bad relay?

 

Turn the mechanical fan by hand and note how freely it turns,then warm up the motor and check it again,of course with engine off. It should have some drag to it or harder to turn.
The only thing I can think of why po would have electric fan running all the time is if they had a cooling issue or it would not come on when it was suppose to. It is possible that the sensor is bad,relay or that the ac does not work or has lost its charge.
Hope this helps.

 

This is how I tested mine from information I found on this site. The temp guage on mine was creeping up everytime I was in stop-and-go traffic.

Start the engine and let it run till it reaches operating temp.
Have someone turn the engine off while you are watching the mechanical fan.
The mechanical fan should stop almost immediately (or close to it).

Mine kept spinning for about 5 seconds after the engine was turned off.

 

My fan will turn on for about 5 seconds and the shut off and then turn back on over and over regardless of the engine temp... Perhaps yours was doing the same? Its probably just the relay