Electric fan stays on after car is turned off . . .

OK, I'm loving the new fan but here is a little doozy. I drove into work today, AC on and temp was reading a little over 195. I turn the car off and notice that the fan stayed on. I don't know if it's supposed to do that or not. Yesterday my temp was even a little higher and the fan turned off after I turned off the car. I tried to see if the radio would turn on so I pressed the power on the radio and the radio turned on even with the keys out of the igniotion. I jiggled the keyhole a little and the radio turned off but the fan stayed on. Turned the key cylinder on and off and still wouldn't turn off. Decided to leave it alone for 10 minutes. Come back to the car and still on and the temp was readying 160, so I tried removing the fuse out of the relay but still wouldn't turn off. So I disconnected the negative battery terminal and it turned off. Reconnected the battery terminal and it turned on again. So the car is sitting with the negative disconnected. Don't have to drive it til later on tonight.

 

What about your A/C power lead? Any chance that is a constant hot and you left your A/C in the "ON" position?

 

I forgot to mention that, I check the AC and it was definitely tuned off. I clicked the switch on and off to make sure. I am not a 100% sure where the power from the AC comes from, need to check that before I can tell you.

 

did you use the type of relay with an override switch? make sure that is turned off as well? hope you get it figured out....

 

I just talked it over with Bryant. We're thinking maybe it's the larger relay I have, that's an older one I bought off of Jay a while ago. I let it sit around for some time, maybe it just died. I'll replace it and see what happens.

 

My fan does that too, because of the temp probe and the way I have it wired, My fan will run for about a min or so after I turn the car is off only when it's hot out and the temp is still above the 180 setting on the probe.

 

yea I figured if it stays on for like 5 minutes that's cool but the temp was below 160 and the thing was still on and it was over 10 minutes, that's what concerned me. Maybe I should have waited longer but I guess I'll know when I go back to plug it in.

 

If you have an adjustable tempature probe... maybe you have it adjusted to low

 

Got more info.
Got back to the car today at 10p, engine totally cold. Hooked up the negative battery terminal and the fan turned on again. Tried killing the power to the fan by disconnecting the quick-disconnect plug we installed onto a power wire feeding the solenoid but that didn't work (weird) so then I took out the big fuse that goes from one of the solenoids to the starter relay and that killed the fan. I started the car and plugged the fuse back in

Even more weird, after driving the car and arriving home I turned the car off and the fan turned off. Turned on the key all the way to ON without starting the car and the fan kicked on. Turned the switch to off and fan turned off.

Is that still a relay issue?

 

Anything is possible. Your gonna have to trace this one. Get the test light out.
I would probobly wait till the fan is staying on like you said. Then disconnect the fan at the fan. Reconnect the fan to see if it still turns. If it does then disconnect it again and work your way back. If it turns off, I MIGHT suspect the fan.

 

Its probably just the relay hanging up. Pretty common problem for them once they get some age on them and the contact points get a little pitted from many cycles.

 

I have my fan coil wired to the thermostatic switch so my fan will run with the key off.

 

Dennis, I have my...relay, ground wire...ran through a...2 prong temp. sensor...in the intake. at 185 the sensor will close and go to ground, activating my relay.
question: can i run my...power wire... through this sensor? that way it should run untill it gets to the low side of the sensor (170) and goes open.
my electric waterpump is wired to the same relay. if i leave the switch on it will cool down in 30-32 seconds and shut the fan/waterpump off.

... DFF...

 

yea, I am gonna try to put a new relay on and see if it'll work

 

As long as it has 2 leads coming out of it, you can run a power line through it. The power line to the coil of the relay, not the power line to the fan. Best way to tell for sure is bring the car up to temp (when the fan would be running) and remove the wires. Then take an ohm meter and measure the terminals to the base of the sensor. Should be infinity.