i have an 07 dodge caravan, and last night the rad fans stayed on after turning the vehicle off. I ended up having to pull the fuse out as to not kill my battery, I pulled the relay and replaced it with one off an 04 caravan, and that seems to have fixed it. but im not 100% sure, is there anyways to test if its working now? the check engine light is still on, I ran codes this morning and all it comes up with is coolant system issue

 

i forgot to mention, the original relay was running the fans even when not being grounded

 

You could have a bad relay or the fans are shorting out. The fans should go on at 212 temp., and shut off at 190.