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CBeluga3 04-18-2012 10:04 PM

fan relay
Hello everyone, I have had issues with my fan relay for over a year and a half now. I have replaced it 6-7 times, from the auto part store, and from jeep itself the laat 4 times. we changed the fan motor as well. The last relay we put in blew out within a day, my husband finally got so fruatrated that he ran a separate toggle switch that runs the fan manually. It works great however, we would like to fix the problem, especially since the check engine light stays on permanently now and it won't pass inapection because of that. someone recommended chamging the computer, could the computer keep blowing the relay? What else could be the problem? any ideas?Any help would be greatly appreciated!

Frango100 04-19-2012 10:41 AM

Re: fan relay
Normally the problem is the fan motor itself, which is drawing too much current. But since that one is changed as well, it should be something else. Your jeep has the setup with the fan relay under the right headlight, or it has the 2 separate relays in the power Distribution center?
After changing the relay, was it checked that the fan was not continuously running? Also a faulty temperature sensor could let the fan run all the time, but i'm not sure if this would damage the relay that quickly. Maybe a good thing to measure the current draw from the fan, to see if that is not too much ( maybe an other member can chime in with what the normal current draw should be)
Since the check engine light is on, there should be a fault code set. Switch ignition OFF/ON-OFF/ON-OFF/ON and the odometer will show a fault code (or "DONE" when no faults are stored). Maybe that this code will help futher.

CBeluga3 04-19-2012 03:56 PM

Re: fan relay
yes the fan relay is under the right headlight and the fault code just reads for the relay. and no the fan was not running continously either, he put the toggle switch in because without the relay, the fan wouldn't come on and the car would overheat. thanks.

Frango100 04-19-2012 07:48 PM

Re: fan relay
1 Attachment(s)
But are you sure the relay is at fault, or is just the fan not switching on? A faulty coolant temp sensor could have the same effect of the fan not switching on. Eventually some error in the PCM could also cause this, but i would not suspect it to fry the relay.
If the relay is really fried, then there is possibly a shafed wire, which makes a short, or the relay is not connected right?. Attached a schematic which could maybe help.

CBeluga3 04-20-2012 01:00 PM

Re: fan relay
ok, we will check that and let you know. thank you so much

guitarguy2186 04-20-2012 01:13 PM

Re: fan relay
I had the same problem with my jeep, they suggested the same thing as changing the fan motor because it was going bad, i didnt have the money for it at the time. I looked at the wiring harness that connects to the relay and it was slightly blackened like a short occurred. I changed the wire harness that connects into the relay (purchased from the dealer for 20$ i believe). The relay hasnt blown in 2 years and i didnt have to change the motor. hopefully this could be a cheap alternative that may work for you

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