Ok so my newest 90 xj has the motor out of a 96 and just took it out for a ride and noticed the temp gauge alil high popped the hood & aux fan not coming on also the ac compressor doesn't kick on either if thats related at all with this year. any idea if the fan is compatible with the newer engine or will I need to run a switch for it?aux fan comes on fine with a jumper wire

 

im not sure. maybe try OEM tech?

 

relay on drivers fender well good power at ac pressur switch?