St.AngerXJ

Hey everyone. IM new to the forum; even thoug I've had my xj for years.its a 98. I am having an issue with the electric radiator fan and i did try searching it. The fan stopped working and so far i have changed the relays for the fan and a/c clutch;the fuses in the kick panel and engine bay; the fan itself the temp sensor and i checked the grounds on the wiring charness. I DID however notice the conector from the harness to the fans wiring looked a little beat up; so i tried splicing them directly together; and nothing.Still haven't figured it out yet. The fan does not engage with a/c on and does not engage with high temperature. Any ideas??? Thanks

tjwalker

You certainly have addressed almost all of the usual suspects.

Have you inspected every inch of wiring? I'd test for power at different points along that entire section of wiring leading to the fan.

It also could be a problem with the computer itself. I'd try a salvage yard one.

St.AngerXJ

Thank for the quick response haha. Yeah i pulled the loom off and checked everything out. I didn't notice anything. Probably wont hurt to check again. I just need to get a tester. I was also thinking it as a computer issue but ill need to test the wiring first.

jomps

have you tested the fan?

St.AngerXJ

Yes and the old one was only a few months old but i replaced it with a brand new one from rock auto. Still no difference -_-

mentalbreakdown00

Ok the fan is controlled by the ECM by grounding the relay, and for some reason on a lot of cherokees lately I have seen the transistor in the ECM go bad and not ground the relay. You could test my theory by grounding pin the coil of the rekay and it should click on and the fan run. Next you would need to have a competent scan tool and try to make the computer turn the fan on, if it does then, you have a deeper issue, if not then your problem is most likely the ECM. Ley me know if you need further help.

St.AngerXJ

Thanks IM checking it out right now.

St.AngerXJ

Looks like your right. Its the only option i got left haha
I tried listening for the click from the relay while engaging the a/c and i got nothing.IM probably going to hit the junk yard for an ecm. Seems like its the cause.

St.AngerXJ

Thanks for your input guys. Ill let you know how it goes.

mentalbreakdown00

Well you should test it first by grounding the a/c relay, if everything works then you find someone with a good enough scan tool to force the fan on, if it won't do it then you know you have a bad pcm

St.AngerXJ

IM might just hook up a toggle switch to it. Im short on time and i gotta drive pretty far tomorrow. Lol

DFlintstone

You do know the temp it comes on at is real high...217* or so. Also (on my old 90 renix), mine won't come on with AC because my refrigerant pressure is too low. Since the AC is not working and the compressor clutch isn't engaging it doesn't trigger the E-fan. Sounds like you figured it out, just wanted to mention that. You did try with it on defrost as well.....

I'd make sure the sensor is telling the your PCM to ground the fan relay. I did see somewhere you can use the correct resistor to mimic the sensor closed...IdK! I guess you can't just connect the sensor wires directly.

mentalbreakdown00

I gronded my relay so when the key comes on the fan is on....