Temperature Gauge not working, AFM inoperable, radiator fan stuck on h

ChrisGu · May 9, 2020

Hey so having the same issue. When I start the truck the Temp gauge On the dash seems to works goes all the way to the right and then back flat. After that it does not move and right away the radiator fans kick on in high mode. My coolant levels were low last week, I added coolant it ran fine for a week. Not sure if this can be an air bubble after all this time or do you think it is the thermostat?

JimCost2014 · May 9, 2020

41 minutes ago, ChrisGu said:

Hey so having the same issue. When I start the truck the Temp gauge On the dash seems to works goes all the way to the right and then back flat. After that it does not move and right away the radiator fans kick on in high mode. My coolant levels were low last week, I added coolant it ran fine for a week. Not sure if this can be an air bubble after all this time or do you think it is the thermostat?

Welcome to the site.

Can you share any more info about your truck? Make, model, year, miles, engine, history, are you the original owner?

ChrisGu · May 9, 2020

8 hours ago, JimCost2014 said:

Welcome to the site.

Can you share any more info about your truck? Make, model, year, miles, engine, history, are you the original owner?

Yes of course sorry. It is a 2014 Chevrolet Silverado 1500 5.3L

Is there a way to test it? If there is blockage? Water pump? or a sensor?

JimCost2014 · May 9, 2020

7 hours ago, ChrisGu said:

Yes of course sorry. It is a 2014 Chevrolet Silverado 1500 5.3L

Is there a way to test it? If there is blockage? Water pump? or a sensor?

Have you had and CEL's?

Did you change the coolant recently? Do you have a scanner, or an auto parts store close by to do a real time scan to see where the water temp is at while running?

ChrisGu · May 10, 2020

1 hour ago, JimCost2014 said:

Have you had and CEL's?

Did you change the coolant recently? Do you have a scanner, or an auto parts store close by to do a real time scan to see where the water temp is at while running?

it was low on last Saturday I felt it acting weird when I went to put on the AC. I noted it was low so I added coolant and it was fine. It lasted 5 days and now is acting up. The gauge on the dash shows like it’s ice cold. I added it again this morning Very little and the gauge seems to be working again and the fans are acting normal. I don’t think the problem is fixed.

JimCost2014 · May 10, 2020

19 hours ago, ChrisGu said:

it was low on last Saturday I felt it acting weird when I went to put on the AC. I noted it was low so I added coolant and it was fine. It lasted 5 days and now is acting up. The gauge on the dash shows like it’s ice cold. I added it again this morning Very little and the gauge seems to be working again and the fans are acting normal. I don’t think the problem is fixed.

If possible, check the records of the truck.

There was a problem in the 14 and 15's having radiators that would crack at the top edges, bad AC condensers were also a problem.

Maybe take it somewhere and have a pressure test done on the cooling system, looking for leaks. I guess it is always possible your thermostat could be the problem too.

That was one of the main issues with the cracking radiators, it built too much pressure in the cooling system.

Edited May 10, 2020 by JimCost2014

ChrisGu · May 11, 2020

18 hours ago, JimCost2014 said:

If possible, check the records of the truck.

There was a problem in the 14 and 15's having radiators that would crack at the top edges, bad AC condensers were also a problem.

Maybe take it somewhere and have a pressure test done on the cooling system, looking for leaks. I guess it is always possible your thermostat could be the problem too.

That was one of the main issues with the cracking radiators, it built too much pressure in the cooling system.

Thank you that is good to know. I think that may be the issue, because now the thermostat was working fine and so is the gauge. Ive always smelt anti freeze from this truck since I got it in 2014. I took it there one time and they had to replace the hoses going to the water pump, but now I am thinking maybe it was this issue the whole time. I just had it dropped off to get looked at I will see what they say and keep you informed.

Thank you!

JimCost2014 · May 11, 2020

46 minutes ago, ChrisGu said:

Thank you that is good to know. I think that may be the issue, because now the thermostat was working fine and so is the gauge. Ive always smelt anti freeze from this truck since I got it in 2014. I took it there one time and they had to replace the hoses going to the water pump, but now I am thinking maybe it was this issue the whole time. I just had it dropped off to get looked at I will see what they say and keep you informed.

Thank you!

You are very welcome.

Good luck!

Jason Winters · January 28, 2022

Opening up an old thread, but this same issue hit me this morning. Bought a new temp sender, reset the battery and it's back to normal. 2014 Silverado 1500 LT crew cab 4x4 Z-71 package, 5.3, 137K miles. First engine part I've had to replace on this beast, aside from normal maintenance items.

Edited January 28, 2022 by Jason Winters
misspelling

Mark Adams · January 29, 2022

I'm having the problem described by the author.

-Blower motor on high, stays on for a few minutes after turning off the engine.

-Temperature gauge at 0

I see some people are replacing parts and finding that the issue is still happening. I haven't yet replaced any parts, but I noticed that disconnecting/reconnecting the battery "fixes" the issue temporarily for me. If I disconnect and reconnect the battery, and turn the car on again, the temperature gauge immediately shows the temperature (above 0), and the blower is at a normal speed. I think that there may be some bad software going on in addition to whatever hardware is intermittently failing for me. If you replace some parts, make sure to disconnect/reconnect the battery to reset your computer state.

Sethp78 · March 9, 2022

Mark- have you found a resolution yet? I’m having the same issue as all you guys and it’s becoming quite annoying

Unhappy Owner · September 28, 2022

My 2014 did the gauge pegged down & high fan ****** less than a year ago - new temp sensor fixed it then ...... but has recently started this same scenario again now. Sometimes the only permanent fix for these type issues is a new owner !!!!!

I’ve had nothing but electrical issues with this POS the last 3 years - electric rack n piñon went out (stupid stupid high $$ to fix that) then the doors wouldn’t stay looked (BCM & programming bullshit) I’m about done with it & GM’s period

Unhappy Owner · November 6, 2022

Found out that my ‘14 Silverado is a piece of Gdamn ******

Sooooo many electrical issues

P O S

JLW71 · December 31, 2022

My 2015 GMC Sierra 1500 5.3L has been running cool for a while. Temp gauge finally quit registering and the radiator fans wouldn't shut off even with the key out of the ignition. Pulled the fuses since I was at work that morning when this happened. Got a new thermostat (overnight shipped) and sensor from Oriellys. Must be a shortage because no one had one in stock. Anyway, changed both, topped off coolant, and had to unplug the battery to get the gauge to work again. Seems to be ok. I'll keep y'all updated if anything changes. Thank you all for the extremely helpful information. Saved me a chunk of change and a major headache. Happy new year to all.

ben.doyle.37 · January 23, 2023

Hey guys,

dealing with the same issues. Replaced the thermostat and temp sensor, reset computer and still having the same issue. My truck is a 2018 Chevy Silverado 1500 5.3. I’ve also replaced the radiator before this. My brother is a mechanic, he’s going to put the computer on it this afternoon and see if we can find anything as to the reasoning behind this. I’ll keep y’all updated and any advice would be greatly appreciated.