DEF level sensor issue

[RK58]

My 2023 Tahoe DEF level dropped the other day from 1/2 tank to 0 bars on my gauge and a warning of low level on the DIC, I filled the tank and it took 2 gallons so it was reading correct before it died but still reading 0. I have read of issues with the 21 and 22 Silverado needing a new DEF tank because of the level sensor issues. Just wondering if anyone has had this issue, it goes into the dealership this Thursday hopefully it is something simple.

 

[StephenPT]

Sounds like a level sensor failure if it's still reading 0 bars after dumping in 2 gallons. Overall I have not heard of many issues with the DEF level sensor on this platform.

 

[steiny93]

After filling did it show full or still empty?

When towing (so using a lot of def) my wife's Denali will show 0 bars but still have more then 1/2 of a tank of def. When you fill it up it then shows a full tank of def. It has been to the dealer a couple times for this; all systems normal.

What is occurring is that the computer sees that it can't go more then 300 miles on the current amount of def so it sends the warning to the dash with a miles count down, when it does that it must think "well I warned them so I cannot show much def, I'm going to show you zero def" so the tank goes to zero even tho you have more then 1/2 a tank remaining.

When we tow for long distances (>1000 miles) this behavior occurs; doesn't happen on short trips (<250 miles).

Not sure if that is what is occurring for you; but this is supposedly a 'normal' behavior.

 

[RK58]

The technician had to reprogram the tank module all good now.

 

[dbphillips]

Our sensor got stuck at full. Stayed there for maybe 500 miles, then finally reset and quickly dropped to nearly empty. I had been adding DEF, but I think it has been on the low side. I added a bottle and suddenly it was showing full. So maybe that is the new normal for when we are towing, but I would rather it reflect physical DEF level.

 

[MrMike1289]

I’ve experienced odd things with my DEF gauge as well. Someone once said that it’s not a normal sensor and it uses more of a “guesstimate” by calculating the range or something? Anyhow, usually I only experience “issues” when I am towing. Same as you, gauge will show half tank, then suddenly show zero. The first time this happened I got the “low” warning saying I had 300 miles left or whatever, then 5 miles later I received the “critically low - speed will be limited soon” warning. Because of that I always travel with DEF when towing.

Additionally sometimes when I fill the tank (at a pump) the gauge won’t show FULL. Takes a few miles of driving/engine restarts before it reports full. Dealer always shrugged me off when I mentioned this.

 

[RK58]

Well it happened again no real reading on the gauge, light blue bars are gone with 500 miles on it since last issue 3 weeks ago when it was reprogrammed and verified 99% full. My Chevrolet app says no refill needed, so I am thinking maybe if it is a calculation, then that is working but the communication to the bar graph is not. This is a non towing situation this time and also last time it happened. Going back to dealership in a week or 2 and I will have them add DEF to the tank so they can determine the issue. A manager at the dealership last time mentioned just carry a DEF jug in your vehicle at all times, my reply was maybe they should also get rid of the fuel gauge and we all keep jerry cans with us.

 

[Stbentoak]

I dump in a 2.5 every oil change (Appx 6-7K miles) and this seems to always put me in the 1/4 to 3/4 range all the time. Not towing.

 

[Tinbadtin]

Dealer filled the DEF tank full at delivery (at least according to board computer). Filled 3x 2.5 gallon jugs and now at 50% after 11k miles and two oil changes. So basically 1 gallon of DEF per ~1,000 miles. Not towing either.

 

[Stbentoak]

Dealer filled the DEF tank full at delivery (at least according to board computer). Filled 3x 2.5 gallon jugs and now at 50% after 11k miles and two oil changes. So basically 1 gallon of DEF per ~1,000 miles. Not towing either.

That sounds excessive. I've only put in 3 and I'm at 25K miles.