dmax

Newbie to the Forum, but figured this to be this best place to get the answers.

On my 2000 Cherokee, the electric will not turn on, even when I turn the AC on. I’ve replaced both the relay and the temp sensor. I’ve tested the fan at the breaker box to confirm it works.
Based on my experience with my old 1993 XJ, I never had a heating issue, but this 2000 model climbs to 210 pretty fast without the electric fan turning on.

Considering I’m in TX, I’d like to get this thing working for the heat shows up, and without having to go the dealership for them to troubleshoot.

FYI, I’ve followed most of the instructions at the following link without any success, http://www.lunghd.com/Tech_Articles/Cooling/Electric_Fan_Diagnosis.htm

Any direction would be greatly appreciated.

Thanks,

djb383

There have been posts that '00-'01 XJ efans turn on when the a/c refrigerant pressure reaches X psi and/or when coolant temp reaches 223F. Supposedly the system can be re-programmed by the dealer so that efan activation can be like '99 down XJs.

dmax

Update, changed out the 195 thermostat with a 180 in hopes to keep the temps down. However, the electric fan still will not come on, even with the AC.

I spoke with the dealership and they said something about the radiator fan module could be out. When I asked what this was, I was told that it’s the electric fan assembly. BUT, I’ve confirmed the fan to work by bypassing the relay and hooking straight to the battery.

Anyone else had this kind of wired issue with the e-fan on the 2000 model Cherokees?

j-rod

arent there two temp sensors that control the fan engaging? also the efan doesnt come on at 210. 210 is the normal operating temp. the fan kicks on over 210 and off when back to 210

thorguy57

There are two fuses for this system. Did you check them both? They both need to work for your fan to turn on.

thorguy57

One fuse is in the junction block, the other is in the PDC.

dmax

From everything I've read and when I spoke with the service dept at the local dealership, the efan is supposed to come on when the AC is turned on and when the temps get to 210 or 218, I forgot what he said.

I've beat my head into the wall on this and just would like to avoid having the dealership screw me over.

thorguy57

Yes it is suppose to come on whenever your ac is turned on. If one of the two fuses are blown in wont turn on. Check the fuses and tell me what you find then I can help you more.

dmax

I've checked all the fuses in the engine compartment and replaced the relay without any success. What other fuses are you referring to?

thorguy57

It says there is a 20 amp fuse in the junction box in the cab somewhere. Check all the fuses in there. Also pull the connector off the fan and make sure one of the 2 wires has a good ground. But check all the fuses in the cab first. This one has to be good otherwise the fan will not turn on.

dmax

All fuses are good inside the cab and in the power distribution under the hood. Any other ideas?

thundaluvin

First you need to put a 195 back in. otherwise you will never know if the fan works when it's supposed to. secondly, run a hot wire to the fan itself and make sure the fan itself works. if the fan works with a hot wire run to it, it's either a sensor or a relay. 210 degrees is where the jeeps like to run. some fans only turn on at 218. do those two things first. then diagnose the problem.

dmax

The 180 thermostat was put in to help compensate for the efan not working. The fan should kick on when the AC is turned on, or if it hits the 218 mark, but doesn't happen in either situation.

The efan works, I’ve connected it direct to 12v and also jumper’d at the fan relay position in the power distribution box. So, the fan works direct from 12v and from the relay position.

Does the efan have any type of module or diode that could be out?

thorguy57

The module is just the ECU grounding the Relay for the cooling fan. Try to ground the relay to a ground and see if it kicks on.

dmax

While the engine is running, and the fan relay in place, I unplugged the radiator temp switch and the fan came on. Plugging the switch back in turns the fan back off.

I've tested the ground at the relat connection and confirmed it's good. It's clear my problem is somewhere that the AC connects in?

What is fan diode assembly?