mrrecon4

99 cherokee sport. Is the elec. fan supposed to come on about every 30 seconds while idleing. Engine warm one line below 210
thanks

freegdr

Is heater or defrost on then yes.

djb383

Compressor/efan engage/turn on when the vent selector is in any of the positions circled in yellow. Rapid compressor cycling/efan on/off can indicate low refrigerant.

CCKen

Where do you live, and what are your outside air temperatures?

mrrecon4

i live in tacoma wa, right now its staying around high 30 to high 40. it is has been doing this since i have own it. latley i do have a colant leak i am looking for plus i will check out where i have the switchs
thanks

CCKen

The AC compressor will engage when an AC/Defrost/Defog selection is made and the outside air temp is above 30*F.

Rapid cycling can be caused by low refrigerant service, as mentioned above.

freegdr

Isnt the 99 have the pressure switch that only activates fan when high head pressure exist..

MonacaYankee

No it's not. My electric fan on my 99 won't come on at all unless it's 80+ outside and the jeeps not moving. The 94s fan only has turned on during the dyno emissions test.
I'm going to install a switch for the fan on my 94.

freegdr

Im referring to ac being on ...

MonacaYankee

Well I haven't used my ac in a month. The compressor cycles about every 30 seconds with the fan.

And high head pressure??? The fan only turns on when the coolant temp is at 218F or with the ac.

freegdr

If your running heat or defrost fan cycles on and off. It supposed to do that .

mrrecon4

thanks guys went out and just put the switch to the floor. and the fan did not come on so every thing is good there still will check out ac latter in the year and i do have a leak in the colant so have to find that but atleast now i know the fan is working right

djb383

I believe '00-'01 XJs cycled the efan with a combination of where the vent selector was set AND refrigerant pressure and/or coolant temp. '99 down XJs turned on the efan when the compressor cycled on and/or coolant temp.

Fred/N0AZZ

You as well as several other are correct I do believe. I know for a fact my 99 do that exact same thing, I love the amount of information available here. I should have said "Correct Information" thank you.