DEF issue

[My3Girls]

Light came on again !!!

 

AT4 Forum Fav 👍

Truck Tire Repair Kit - Grab one through Amazon!

[Willrose64]

I should of said this first, serv def system came on first with only 1 bar on the graph for def, I filled it and serv engine light stayed on, got home and truck sat for an hour, now no lights or anything is on, also the gmc app said the same thing now it says everything is good !! My bad !!

I am having a similar issue but only when I tow. The gage will go from 75% full to the red warning level with no readings in between. I also had an issue when it said that I was near empty.......went to fill it up and could only put about 1 gallon because it was actually full! Even after filling the gage did not move off of empty.