So I just got my xj, all stock 98 limited. There is a new 180 thermostat in it so my jeep hasn’t gotten hit enough for the electric fan to pop on. However, I feel like the fan doesn’t work and one day we found out that when we pull the fuel pump relay fuse in the engine bay while the car is off, the fan will turn on. Any ideas? Weird situation every one of my jeep friends has no idea what is going on there. Thanks

 

The electric fan should turn on at about 210 -215 or if the A/C is on and the high side pressure gets high enough and I don't know why it would on with that fuse removed , but if you unplug the temp sensor the fan should turn on but you will set a code and turn on the check engine light .

 

The electric fan should only turn on over 220. 210 is normal operating temp, the cooler 180 thermostat can cause issues, but that's a whole other ball of wax.

 

Clearly it does work, whether it comes on when it should is another matter.

Still, as tech's explained, it's easy enough to check.

Oh, do yourself (& your XJ) a favour & replace that thermostat with the right one.