2016 temp gauge not working and fans running high speed

[TChas999]

Turns out I had to replace the thermostat as well, about a month after I replaced my temperature sensor.

 

[L8T BURB]

Turns out I had to replace the thermostat as well, about a month after I replaced my temperature sensor.

In your case, and most others, the original sensor likely never needed replaced. The way the thermostats fail in these always makes people want to target the temperature sensor. Trust me, I was one of them.

Mine happened about a year ago, and I only figured out the thermostat was the issue just by dumb luck and shooting the ole parts cannon at my Suburban. Thankfully I was successful early on. Middle of last year, there was essentially no info on the forums about this issue.

 

[DCS3]

Follow up….
Changed the thermostat and sensor with GM parts, car is back to normal.
Thank you all for the advice.

 

[TimT517]

Hi all, long time lurker but first time posting. I have a 2016 Tahoe LTZ that has a new issue that happened tonight. The wife and I had an appt about 7 miles from our house. On the way to it everything was fine, however on the way home about halfway I heard the fans kick on. Did think anything was wrong just the fans running. Then I noticed the temp gauge hadn't move from 0 degrees. I stopped to check to see if it was actually getting hot. It was stone cold. The overflow tank was at normal level and just barely warm. We finished the ride home pulled in the driveway and I checked again, still cold! Also the fans were running full tilt engine off. I restarted it a couple of time no change. fans on and temp gauge didnt budge. As I was looking for the fan relay to pull it the fans shut off after about 10 minutes with the engine off. Also no CEL light. Any Ideas before I waste more money at the dealer? Thanks in advance!

Start with a cold engine. Unplug the negative battery terminal for about 10 minutes to reset everything. Start your vehicle and let it warm up. Drive the vehicle and pay attention to the temperature gauge. The temperature should increase to and hold at 210 degrees. If it doesn't make it to and hold at 210 degrees you need a new engine thermostat. The thermostat is sticking open sometimes and triggering the fault that makes the cooling fans come on and stay on, also leads you to believe you need a new coolant temperature sensor. Replace the thermostat!!! If your vehicle's temperature never comes up( above the 0 line) after you've reset the computer then you need a coolant temperature sensor! Unfortunately, after you reset the system by unplugging the battery it might be a couple of days or even a week/month before the event happens again, but keep watching that temp gauge and if ever a time it doesn't make it to 210 degrees and those fans come on and stay on, you've found your problem(Thermostat) The quick solution is to replace the water coolant temperature sensor and the engine thermostat at the same time and don't forget to unplug the negative battery terminal to reset the system before starting the vehicle after you replace the parts. If you forget to reset the system the fans will keep running because the fault will still be stored in the vehicle's computer. Problem solved 100% and you won't have to come back here.

 

[Fless]

Start with a cold engine. Unplug the negative battery terminal for about 10 minutes to reset everything. Start your vehicle and let it warm up. Drive the vehicle and pay attention to the temperature gauge. The temperature should increase to and hold at 210 degrees. If it doesn't make it to and hold at 210 degrees you need a new engine thermostat. The thermostat is sticking open sometimes and triggering the fault that makes the cooling fans come on and stay on, also leads you to believe you need a new coolant temperature sensor. Replace the thermostat!!! If your vehicle's temperature never comes up( above the 0 line) after you've reset the computer then you need a coolant temperature sensor! Unfortunately, after you reset the system by unplugging the battery it might be a couple of days or even a week/month before the event happens again, but keep watching that temp gauge and if ever a time it doesn't make it to 210 degrees and those fans come on and stay on, you've found your problem(Thermostat) The quick solution is to replace the water coolant temperature sensor and the engine thermostat at the same time and don't forget to unplug the negative battery terminal to reset the system before starting the vehicle after you replace the parts. If you forget to reset the system the fans will keep running because the fault will still be stored in the vehicle's computer. Problem solved 100% and you won't have to come back here.

It's best, at least initially, to NOT rely on the cluster gauge for the ECT. Monitor live data with a scanner since the dash gauges are not all that accurate. After that you might be able to correlate the ECT sensor's reported reading with the dash gauge.

 

[Jonmurphy]

Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

You are already receiving sage advice from the knowledgeable folks on this Forum.

Smart guy !! use the catch can always Folks You don't want that crap going back into your spark plugs and everything else Oh no