After a good off-road run in May, my 2000 Cherokee Sport ran great. In Late June on the Interstate, must've caught a rock or something as I had a hole in the radiator. Put in new radiator, water pump, all hoses, t-stat, cap. Noticed no fuse in box for electric fan, so I put one in. Ran fine till about a week ago, the fuse for the fan blew. Old fan had a cracked shroud so we replaced the whole assy with new. New fuse for elect. fan blew as soon as plugged in. Hmmm short circuit. PO has run a wire from underhood fuse box at the cooling fan relay to a switch on the dash. Dosen't seem to do anything far as I can tell. New fan is ok, everything else seems ok. Can't find diagram to ck wiring. So any ideas why the 40 amp electric fan fuse blows as soon as plugged in? Even with no key in ignition.

 

It blows because there's a short circuit. The challenge if finding where the short is.

I'd start by unhooking the dash switch at the relay.

I don't think that's supposed to be a 40 amp fuse, either, which suggests the PO was having a similar problem.

Mostly likely the switch was installed incorrectly, kept blowing fuses, and he upped the size trying to get it to stop blowing (always the wrong thing to do!), and gave up.

It's probably badly wired and shorts intermittently.

 

I agree about what the PO did. On the fuse box cover in engine compartment it does have a call-out for a 40 amp fuse marked for cooling fan. Will dig out my meter and pull out my hair. LOL. By the way, the A/C works great, but the temp starts to climb to 220 in city traffic. Haven't let it get any higher.

 

40 for the fan? Hmmm. I think my 97 is a 15 (but that's just from memory). Maybe the later ones drew more current.

 

2000/2001 PDC fuses:



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Rad Fan Circuits:



.

 

Didnt think fan came on until high ac pressure or high temp on 2000 ?

 

Theres a 2000 to 2001 diag in here...https://www.cherokeeforum.com/f2/coo...nction-133903/

 

RAD FAN 40 amp in the pic would blow even without the key in the ignition sw. Got after it today. The wire the PO rigged up was shorted. It was going into the cooling fan relay in the PDC. Removed the rigged wire, installed a new relay & fuse in the PDC. Let it run the temp up & the cooling fan came on & ran as supposed to. Responses are appreciated as I've been unable to do much on vehicles for years due to various injuries and forgot some things. Anyway, we're back on the road now, working fine. Now on to the shifter in the Charger to replace broken part in it. Does it ever end?

 

Good work and thanks for the follow up.


Cheers

 

No.


But then, you knew that!