CherokeeOutlaw

My electric fans turn on the second I turn my key. They do not respond to any thermostat. Why? Because the previous owner directly connected the power wire to the solenoid!!! Where do I re route that wire in order to have the fans kick on with the thermostat? Please be as detailed and specific as possible...pictures would be amazing!

98 cherokee 4.0

red wire is the fan power


I assume this is where the water pump and thermostat are? I've never worked on a 4.0.

djb383

Could u post pics of what the PO did regarding wiring?

CherokeeOutlaw

not sure what you mean. The first pic of the solenoid is the red wire from the fan that the previous owner connected. It runs from there to the first fan plug then another wire runs from that plug to the 2nd fan plug. It's straight forward wiring, nothing super technical. I just want to know where do I splice that red wire into to have the fans kick on with the thermostat.

djb383

R u saying u have 2 efans?

CherokeeOutlaw

ha ha you sound like I'm not supposed to. Thought that was stock...here, I can takes pics of them and the wires as best I can, but it is dark...

the red wire runs to this connector then it splits into a red and blue wire. one goes to one fan, the other to the 2nd (left to right). both are positive.


for some reason the forum rotates my pictures weird here you can see two fans I'm assuming the PO must have added one because of the intense heat in Yuma.

CherokeeOutlaw

could it be as simple as installing one of these?

http://www.autozone.com/autozone/par...mString=search

djb383

On a '98 XJ the ECU signals operation of the 1 factory efan......if u have multiple aftermarket efans (and no factory belt driven fan) u'll probably need one of those aftermarket thermal switches and just follow the wiring instructions. Do u have A/C?....if so, fans will need to run when A/C is on (to cool the condenser).

CherokeeOutlaw

threw that aftermarket thermostat switch on and it kept blowing the in line fuse of the switch...bypassed it and got it kicking on at about 215-220 till about 207

CherokeeOutlaw

I just noticed what you said about the AC. It has a wire to connect to the AC motor, but I can't find where to connect it. Everything I connect it to is either constant power, power under ignition, or only when the AC clutch circulates. I want it to come in when I turn the blower on and off when off. (obviously)

djb383

The efans should only turn on when the compressor signals them or when coolant temp signals them. Just turning on the blower fan (no compressor engagement and coolant temp low) shouldn't turn the efans on.

CherokeeOutlaw

got it. so i did find a good spot then..thas

CherokeeOutlaw

I was told by a former jeep mechanic that I work with that my Cherokee came stock with duel e fans. Either way, where can I hook at least one of the fans to the ECU to turn on and off. (in detail please) where is the ECU? What's it look like? Etc...

salad

Ehhhh.. unless there's some ultra-special model that nobody knows about, the Cherokee with the I6 had 1 mechanical fan and 1 electric fan. If you have two of em then someone's "upgraded". Though if they went to all that effort I'd kind of hope for a switch inside to turn them off for water crossings

The electric fan should be toggled by a relay in the power distribution center. Me Haynes book here annoyingly doesn't have a number for the relay, but apparently Fuse 5, a 40A, feeds it. For 97+ it looks like you should have Dark Blue/Pink going from the ECU to the relay, and Light Blue going to the fan itself.

ECU is the big aluminum guy with three large connectors: (from some guy's build thread on JeepForum.com)


Power Distribution Center has relays and fuses, long black cover over front right wheel behind the battery: