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Cooling fans won't turn on any suggestions?

Posted: Sun Feb 16, 2020 8:26 pm
by undrcvrppv
I've replaced all the relays under the hood and all the fuses in the fuse box under the hood. The fans will run if I jump them with a 12 volt hot. Not sure what else it could be

Re: Cooling fans won't turn on any suggestions?

Posted: Mon Feb 17, 2020 1:52 am
by smwalker
What year?

And how are you determining they are not on when they should be? Just temp? Or are you seeing a signal to the Relays?

How about when you tun on the AC they come on then?

Re: Cooling fans won't turn on any suggestions?

Posted: Mon Feb 17, 2020 8:02 am
by undrcvrppv
Getting a check engine light. I believe it says fan control module

Re: Cooling fans won't turn on any suggestions?

Posted: Mon Feb 17, 2020 8:03 am
by undrcvrppv
And it is a 2012

Re: Cooling fans won't turn on any suggestions?

Posted: Mon Feb 17, 2020 4:55 pm
by smwalker
Post up the code if you got it but ECM controls the fans on the 11-13 14+ has a module.

Just to confirm there are 3 fuses to check, they all OK?
F32 - EMIS2
FU6 - FAN 1
FU11 - FAN 2
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Re: Cooling fans won't turn on any suggestions?

Posted: Mon Feb 17, 2020 6:02 pm
by undrcvrppv
Will do I replaced all the fuses except the f 32 I will try to get the code tomorrow

Re: Cooling fans won't turn on any suggestions?

Posted: Mon Feb 17, 2020 8:02 pm
by smwalker
If the code is anything about the heated oxygen sensors those are on the same circuit as the cooling fans. That's wierd:

Heated Oxygen Sensor - Bank 1 Sensor 2, B52F Heated Oxygen Sensor - Bank 2 Sensor 2, B75C Multifunction Intake Air Sensor (LFX - LFX is V6 I believe)), KR20C Cooling Fan Low Speed Relay, KR20D Cooling Fan High Speed Relay, KR20E Cooling Fan Speed Control Relay

Re: Cooling fans won't turn on any suggestions?

Posted: Mon Feb 17, 2020 9:21 pm
by Sanford
I would pull the relays out and check to see if you have one socket terminal that is hot all of the time and another that is hot with the key on. Start with the basics.

David

Re: Cooling fans won't turn on any suggestions?

Posted: Sun Feb 23, 2020 6:06 pm
by undrcvrppv
Just want to say thanks to Steve for pointing out the f32 fuse that I had no idea had anything to do with the cooling fans. Problem solved f32 fuse was bad fans now work again

Re: Cooling fans won't turn on any suggestions?

Posted: Mon Feb 24, 2020 8:48 am
by smwalker
NIce!!! Yea that's a hidden one!! Especially since it says F44 on the diagram, good ol GM numbering system.