Chick-N-Picker

89 cherokee 4.0 auto 4x4 81,000 miles

My electric fan doesn't kick on when it's supposed to. It never did. It did kick in with ac or defrost selected but stopped that. If never kicked on at 217.

Either way for now I'm not going to track it down because I'm taking a trip Saturday so I'm just going to hook it to a toggle switch.

What gauge wire do you recommend? What amp toggle switch should I get?

See easy....I think.

CCKen

AWG 12 wire, 50 Amp switch w/o relay.


You're better off using a relay in that circuit to carry the fan current, not the switch.


40 Amp rated mini ISO relay.

Chick-N-Picker

I dont how to hook it up with a relay in the circuit but I do know how to hook up a toggle switch.

djgrayxj

Note from DJ
Have you unplugged the electric fan connector and tried to run it directly from jumper wires from the battery.

djgrayxj

H-D Cooling Schematic

djgrayxj

Note from DJ Also see
Jeep Cherokee Electrical Cooling Fan Diagnosis & Repair from lunghn
http://www.lunghd.com/Tech_Articles/..._Diagnosis.htm

djgrayxj

Note from DJ
Disregard my notes a graphics for my personal use in the schematic I posted in #5

cruiser54

Is the fan switch on the driver's side lower corner of the radiator plugged in?

investinwaffles

Here is a basic diagram to wire a standard automotive relay;
http://image.off-roadweb.com/f/tech/...al%2Brelay.jpg

Autozone should have everything you need. Much safer and more power going to the fan itself it you just use a relay.

I would also recommend 12 AWG wire at a minimum.

BlueRidgeMark

There is no need for 12 gauge wire. That fan is fused at 15 amps, and that fuse is shared by a number of other loads. It probably draws less than 10 amps.

16 is probably just fine. 14 gauge is overkill. I like overkill, so I ran mine with 14.

https://www.cherokeeforum.com/f51/ri...-e-fan-212243/

Chick-N-Picker

Yes it was. I don't know or never could figure out why it doesn't work.

Chick-N-Picker

I used 14 gauge wire.
I bought a 35 amp toggle switch made like this.

http://m.oreillyauto.com/h5/r/oap/si...0947&ppt=C0335

I think ran a red wire from the red battery post to the top screw on the toggle.

I then ran a red wire from the fan yellow wire to the bottom screw on the toggle.

I then ran a ground wire from the fan to a bolt and a separate ground wire from the middle screw on the toggle to the same bolt.

I used an inline 30 amp fuse on the red wire.

It did not work. It blew the fuse immediately. The fan never came on. I took the inline fuse completely out and straight wired with no fuse. And when I turned the toggle the fan still didn't come on and the my lights got dim and the wires got hot immediately. I turned it off fast.

So apparently now I can't hook a toggle up correctly.

The fan does work. I tested on battery before.
I will now read the relay article.

Chick-N-Picker

I just thought. Two ground wires I ran were not to a know ground. It was just a bolt. Could this have caused it not to work and make the wires get hot.

cruiser54

Key on. Unplug the radiator switch. Jumper the terminals on the harness side of the connector to the switch. What happens? This ain't rocket science.....

Chick-N-Picker

The fan came on.
It's rocket science to me at this point on my life but I'm learning a little at a time.

EDIT: I'm supposed to be taking a trip tomorrow and will be driving through a bunch of small times.

I'm afraid in traffic lights it will overheat especially since it's going to be 100.

Would it be ok/safe to drive with a paperclip or jumper wire for a week.