Engine is overheating because the cooling fan is not working

2014 CHEVROLET MALIBU
75,000 MILES • 2.0L • 4 CYL • AUTOMATIC
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UHSNOEBIRD
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I know for a fact that the fuse, relays and the fan motor are good. When I turn on the air conditioner the drivers side fan comes on but the passenger side fan doesn't come on at any time.
When I hot wired the passengers side fan and it will work.
It must be some kind of sensor or similar part that's stopping the fan motor from working.
I need a wiring diagram of the electrical circuit of the fan motors for the passenger side and drivers side circuits.

Car is LTZ model
Jul 17, 2019 at 5:58 AM
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ASEMASTER6371
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Good afternoon,

I attached a wire diagram. Check the fuses listed for power with a test light or voltmeter. Make sure there is power. Check the 2 fuses I circled for power.

Roy
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Jul 17, 2019 at 2:51 PM
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UHSNOEBIRD
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It has power at these fuses, what else could it be ?
Jul 31, 2019 at 5:47 AM
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ASEMASTER6371
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Okay, go to the relays. remove the relays and turn on the key. Test for power at the pins in the fuse box where the relay plugs in. Let me know the voltages and what pins.

Roy
Jul 31, 2019 at 1:03 PM
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UHSNOEBIRD
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The computer is not sending the ground back to the relay that energizes the fan is what someone has said,we are not sure what all is in the circuit to make the fans work.
Are there any sensors in the radiator or on the head that plays a part in the fans working the correct way, that you know of ?
Jul 31, 2019 at 2:39 PM
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ASEMASTER6371
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The only sensor is the coolant sensor.

You should also verify voltages to the relays as I suggested.

Remove the connector while the engine is running and see if the fans come on.

Roy
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Jul 31, 2019 at 3:02 PM
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UHSNOEBIRD
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Roy give me a little time I'm trying to get this information for a friend so it might be a day or 2 before I respond back, so be patient. Thanks for your help.
Jul 31, 2019 at 7:11 PM
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UHSNOEBIRD
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Should the fans come on once this connector is removed ?
Jul 31, 2019 at 7:43 PM
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ASEMASTER6371
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Yes, they should.

I will be here when you return.

Roy
Aug 1, 2019 at 1:42 AM
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UHSNOEBIRD
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We disconnected coolant sensor and started the engine and the drivers side fan worked but passenger fan didn't work. When the engine was turned off the fan kept running, had to remove the fuse to stop the fan. Let me know what you think.
Aug 1, 2019 at 8:35 PM
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UHSNOEBIRD
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Roy when we disconnected the coolant sensor it made the check engine light to come on but we never checked ( diagnostic tester ) to see if it was the engine coolant sensor code but I'm sure it was.
We disconnected the battery to erase the code.
Do we need to check the relays like you mentioned before for voltage at each pin or connection ?
Aug 2, 2019 at 3:39 PM
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ASEMASTER6371
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Okay.
Aug 2, 2019 at 4:26 PM
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UHSNOEBIRD
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What do you want us to check? the relay voltage or does it show you the relays are good since the fan came on when we disconnected the coolant sensor. Tell me what needs to be done now if you don't mind. Thank you
Aug 2, 2019 at 6:59 PM
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ASEMASTER6371
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Replace the coolant sensor. start there.

If the fan came on then the circuit is good. That leaves the sensor.

Roy
Aug 2, 2019 at 9:43 PM
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UHSNOEBIRD
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Roy, there was no check engine light on prior to disconnecting the coolant plug in but when it was disconnected the check engine light came on.
Aug 3, 2019 at 5:12 AM
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UHSNOEBIRD
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Roy, let me add another thing to this. the cooling and heating gauge is working but I'm not sure if that matters.
Aug 3, 2019 at 6:15 AM
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ASEMASTER6371
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The light came on from disconnecting the sensor.

The gauges can be working normally.

Roy
Aug 3, 2019 at 6:41 AM
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UHSNOEBIRD
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I'll have him to replace the coolant sensor, is that what you recommend ? Thanks
Aug 3, 2019 at 2:26 PM
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ASEMASTER6371
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That is where I would start, yes.

Roy
Aug 3, 2019 at 2:31 PM
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UHSNOEBIRD
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Will let you know the outcome. okay, thanks.
Aug 3, 2019 at 3:08 PM
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ASEMASTER6371
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You are welcome.

Always glad to help.

Roy
Aug 3, 2019 at 3:11 PM
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UHSNOEBIRD
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Roy, let me ask you one more question, is there another sensor possibly located in the radiator ?
Aug 3, 2019 at 3:21 PM
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ASEMASTER6371
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No. That is the only one that controls the fan operation.

Roy
Aug 3, 2019 at 3:31 PM
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ASEMASTER6371
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Did you send another response? I got an email but no information.

Roy
Aug 3, 2019 at 3:41 PM
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UHSNOEBIRD
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Roy, I think I typed the word (okay) , telling you I understood.
For some reason or another it didn't show up. Thanks again, will let you know the results later, might be a few days but you will hear from me.
Aug 3, 2019 at 3:53 PM
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ASEMASTER6371
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Sounds good.

Roy
Aug 3, 2019 at 3:54 PM
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UHSNOEBIRD
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That coolant sensor done the job, got the fans going.
Does that coolant sensor have a thermistor in it ? Thanks a lot
Aug 6, 2019 at 4:43 AM
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ASEMASTER6371
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No. It is temperature sensitive.

Roy
Aug 6, 2019 at 5:02 AM
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UHSNOEBIRD
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Let me ask you another question on another vehicle, it's a 1991 Jeep Comanche 4 cyl. 2.5 L engine.The vents doesn't change like they should form the defrost position to the floor and to the vents. Does this vehicle interior air flow work off of vacuum or does the vents work off of some cable or do you know ?
Aug 17, 2019 at 8:19 PM
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ASEMASTER6371
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Rules of the site are 1 vehicle per question.

I would be glad to help but you need to start a new question all the way in the beginning.

Roy
Aug 18, 2019 at 2:19 AM