Grand Cherokee 01 Fan Running with Key OFF

[erick0071]

My Jeep Grand Cherokee Laredo 2001 4.0lt. motor. started having some problems two days ago. The fan stopped kicking in and I tougth it was the fan relay again since i have replaced before. But i got another one and the fan still wont kick in ...the funny thing is that it will run with the key off ..whenever I turn the car off the fan will kick in and stay on. I tried to find a short somewhere but cant seem to find anything. I would like to know what else could be causing this aside from the relay since i have 4 diferents and they all do the same thing so i am pretty sure is not the relay this time. Could anyone point me in the right direction. Could a bad Powertrain Module be a problem. or should i look somewhere else.

[Bob D.]

Well, the PCM tells the relay when to turn the fan on but my guess is the relay is wired wrong, shorted etc.
Test the continuity of the fan/relay circuit.

Note: If you have replaced three relays on a 2001 I would check the currant draw of the fan.

[erick0071]

Well.. cant seem to find a short but will look harder. Is there any place in particular to look closer? I also checked current draw of the fan as the last post recommended and it was around .50 amp ...is that ok? I will be willing to try anything you would suggest and any tips on how to find a short in such a tangled wiring.

[Bob D.]

Originally Posted by erick0071

Well.. cant seem to find a short but will look harder. Is there any place in particular to look closer? I also checked current draw of the fan as the last post recommended and it was around .50 amp ...is that ok? I will be willing to try anything you would suggest and any tips on how to find a short in such a tangled wiring.

Then the fan relay has failed and you will need to replace it.

[hulkmn069]

i agree when my relay went bad that's what it did was run the fan with everything off till it killed the battery. i had to pull the plug until i replaced the relay