My 06 Pac limited had a dead battery the other day. Put jumper cables on it and immediately the radiator fans came on at full speed without the key even in the ignition. The car was sitting overnight so it was cold. Ran the car for a while and the fans remained on when I shut the car off. They stopped after a minute but would come back on intermittently. I could hear (and see the fans) looking like they were going to start but the fans would just move a little then stop. I drove the car a while and shut it down. All seemed normal and the fans stopped when I turned the ignition off. About 30 minutes later the fans started again with the car just sitting in the driveway. They ran for a minute then stopped.. I suspect possibly the fan relay but not sure. What could possibly cause the fans to run with the ignition off? Can't seem to find anything about this issue in old posts.

 

Will need to troubleshoot w/ a multi-meter, tracing back into the computer controls.
Info regarding the controls posted here: https://www.chryslerforum.com/forum/...-cycling-29378 .
Wiring diagram for the fans attached.

PS - if the computer controls are too much of a pain in the wallet, you could simply install a "slave relay" to activate when the key is "on". Just a cheap work-around to consider....

 

Thanks for the reply, but before I go that route I'm going to see if replacing the relay does the trick. From what I have read with others that have had this issue, a couple people claim that only thing that could turn the fans on with the ignition off is the relay being stuck on. Don't know if this is a fact but it makes sense being that there is a hot wire to the relay that always has voltage even with the ignition off.. I suppose it could be possible that the PCM could send a signal to the relay with the ignition off but I'm not experiencing any other issues and this will be a real cheap fix if it works since I already have a relay from one of my last 2 Pacifica's which I stripped before hauling off to the bone yard. I have a stock pile of Pacifica parts! I just replaced the relay today. I'll update if it fixes the problem. Thanks!