RADIATOR FANS STAY ON

kellfree · February 18, 2021

On 1/27/2021 at 1:44 PM, MrMiller said:

I was having the same issue with the cooling fans being on full speed when turning off the vehicle. The temp gauge was pegged at the bottom at 160°F. I would have to disconnect battery to turn them off. This only happened intermittently with no clear reason for it happening. Dealer found a "stuck open" Thermostat and changed it out which they say is the reason for the fan staying on after turning the vehicle off. This was just today 1-27-2021. We will see if this takes care of the issue and I will update later...

MrMiller, Has it been operating correctly since 1-27-2021?

LLyon · June 10, 2021

2015 gmc 5.3l Yukon

fans run upon start at full speed and remain on for roughly 10 m after shutdown.
changed thermostat and temp sensor with no change.

Do I need to have the computer reset?

AC is not blowing cold.

Angel Soto · July 11, 2021

So what was the outcome I want to prevent this from happening by replacing necessary parts . Also Does anyone have a link to the oem specs of the cooling fans for the 2014 5.3l want to upgrade mine to maximize cooling I live in California it’s set to be 114 f all week

Timbooo · July 14, 2021

On 10/29/2019 at 8:15 AM, obregon32 said:

I drive a 2014 Silverado 1500LT 5.3L V8

I noticed my radiator fans stayed on during my 20min drive to work, the ac was not on. temperature gauge did not move from 160*. After i parked and turned the truck of the fans still stayed on. So i started it back on for 20 sec. turned it off and the fans turned off. Another thing, i turned my ac to cold, but for some reason it doesn't get cold while the temp is at 160* and the fans are running non stop. I got home didn't mess with it, the next day everything was fine, ac was blowing cold, temp gauge actually read the temperature. the fans did not stay on. i get off from work and it starts doing the same thing. My brother said it might be a relay, i googled info on this and asked people and many said its probably a relay. i went to the auto-parts store told them what the issue was, and they sold me an ac control relay, which is #68 on the relay diagram on the fuse box. Has this happen to anyone else? my truck is no longer under warranty and i'm not trying to pay a lot of money to a mechanic unless i have to. any advise is greatly appreciated. Thanks.

Fyi i did a check engine light check at advance auto parts, they did a reset on my truck, i got home disconnected the battery and changed out the ac control relay. im waiting to see if it starts acting up again hopefully not.

My 2015 Yukon just started doing the same thing....

antonio burgos · August 1, 2021

On 1/27/2021 at 11:44 AM, MrMiller said:

I was having the same issue with the cooling fans being on full speed when turning off the vehicle. The temp gauge was pegged at the bottom at 160°F. I would have to disconnect battery to turn them off. This only happened intermittently with no clear reason for it happening. Dealer found a "stuck open" Thermostat and changed it out which they say is the reason for the fan staying on after turning the vehicle off. This was just today 1-27-2021. We will see if this takes care of the issue and I will update later...

that fix your problem?

I'm having the same problem right now, and I can't find any solution

gonzoid · August 9, 2021

On 10/29/2019 at 6:15 AM, obregon32 said:

I drive a 2014 Silverado 1500LT 5.3L V8

I noticed my radiator fans stayed on during my 20min drive to work, the ac was not on. temperature gauge did not move from 160*. After i parked and turned the truck of the fans still stayed on. So i started it back on for 20 sec. turned it off and the fans turned off. Another thing, i turned my ac to cold, but for some reason it doesn't get cold while the temp is at 160* and the fans are running non stop. I got home didn't mess with it, the next day everything was fine, ac was blowing cold, temp gauge actually read the temperature. the fans did not stay on. i get off from work and it starts doing the same thing. My brother said it might be a relay, i googled info on this and asked people and many said its probably a relay. i went to the auto-parts store told them what the issue was, and they sold me an ac control relay, which is #68 on the relay diagram on the fuse box. Has this happen to anyone else? my truck is no longer under warranty and i'm not trying to pay a lot of money to a mechanic unless i have to. any advise is greatly appreciated. Thanks.

Fyi i did a check engine light check at advance auto parts, they did a reset on my truck, i got home disconnected the battery and changed out the ac control relay. im waiting to see if it starts acting up again hopefully not.

#68 is the starter relay

Bobbie78 · October 11, 2021

I have the exact same problem. It doesn’t do it all the time, about 2x a week. It did it during the spring and then didn’t do it all summer till now. Temp gage will just go to 160 and cooling fan will come on out of the blue. I will have to pull over somewhere and turn truck off. I then disconnect battery for a few minutes. I reconnect battery and start the truck and we’re back to normal with temp gage reading 210. The engine light does not come on unless I drive too long without resetting it. My husband has changed out relay already and it didn’t fix it. My truck is a 2014 Silverado 1500. If anyone knows how to fix this Please let me know, Thankyou

Joshua Mccoy · October 29, 2021

On 10/29/2019 at 10:32 AM, ksiesel said:

Could the reason for turning the fans on when the coolant temp doesn't come up be a fail safe for a failed in range coolant temp sensor? By turning the fans on, you prevent engine overheat in this scenario.

Back in the days of a belt driven mechanical fan clutch, this wasn't needed as the fan clutch was reacting to the heat coming off the rad and they were designed to fail full on.

RE // i am now facing the problem with my 5.3L V8 gmc sierra 1500. the temp wasn’t coming up and just sat at zero, i pull over and turn the truck off and the fan still went for another 20 minutes. HOW did you did this.?

Bobbie78 · November 2, 2021

On 2/18/2021 at 12:16 PM, kellfree said:

MrMiller, Has it been operating correctly since 1-27-2021?

Awesome, gonna go get one tomorrow… Thankyou!!!

Dcwilliams1980 · December 30, 2021

2015 Silverado 1500 LTZ 6.2L

Last month I noticed my temperature gauge was pegged at an 160 and the fans were running at a very high rate while driving. When I turned off the ignition and removed the keys, they kept running at a high rate for around 2 minutes. I read in some forums and they said it was probably the temperature sensor. I replaced the sensor. It still did it for another day and stopped. Yesterday, the problem started again. I did some more research and found that it could be a thermostat stuck open. I just replaced the thermostat. The truck is still doing it. What else could this be?

elpasomarine · January 3, 2022

I drive a 2014 Chevy Silverado LT 5.3L 2WD. Driving only 20 minutes in December weather, parked then noticed cooling fans running high, and temperature gauge reading 160, then I shut off the truck and the cooling fans continued running for a few minutes then stopped. I started the truck and the fans started up again. The check engine light turned on, so went to get it tested at the auto parts and got a P0128 Coolant Thermostat trouble code. I purchased a Coolant temperature sensor because weather was cold and AC was not being used. Upon replacing the sensor the following day while engine was cold, I started the truck and fans turned on again. I did go and buy a Thermostat kit with housing, disconnected the battery and replaced the Thermostat, restarted the truck and fans didn't turn on and temperature gauge indicating a rising temperature.

GmcSparky · January 10, 2022

P0117 and P0119. Tried new coolant sensor, fixed it for an afternoon, next day fan on high again, found someone had a cavalier that had a bad A/C pressure sensor that told the computer that the pressure was high causing the fan to turn on high. So, went to find they put the sensor by the compressor by the tire wheel well, (great place up in the north with salt, can’t leave a good thing alone and leave up above). While truck was running and fan on high I unplugged the sensor, nothing happened, plugged back in and the fan calmed down to a normal speed. Took back apart and installed some dielectric grease on the connector. So far a week later still good. GM connectors suck. Had problems with my Malibu brake light connectors by dash, before I sold it.

Joflo96 · January 31, 2022

Had this same issue, have replaced numerous sensors/thermostat and relays. It just happens intermittently and never throws a code for anything. Only “fix” is disconnecting the battery for about 30 seconds and reconnecting. It seems the trigger for the issue it a combination of the heater being on as well as it being engaged in the windshield function. Has anyone noticed a similar trigger because I’m not finding a real solution and the dealer can’t identify the issue either.

Sethp78 · March 9, 2022

Has anyone personally found a solution for this yet? Temp gauge intermittently drops to bottom, fans go into full blast mode and stay running after turning off the vehicle.

MMarek · March 9, 2022

I have now replaced the coolant sensor 2x in my 2014 Silverado LTZ and now about to replace it a third time. The sensor first went out about 2 years ago, I just replaced it the second time about a 2 months ago with an ACDelco part. Now the fans are running high again. Could this be the sensor again and if so what could be causing the sensor to go out.

The only way to stop the fans from running at a high speed is to turn off your truck, then restart and turn off. This will cause the fans to shut off.

Edited March 9, 2022 by MMarek