Service Emission System 3.0 Duramax

[GmcJing]

Service Emissions System warning came on this morning at the start of a long trip. Figured it was a regen thing as the car had been only grocery getting for a bit. However, 2+ hours of driving later and it's not going away.
Limping it to a dealer in Dallas now at 65mph, (soon to be 55mph) hoping they can clear this issue.
11,600 miles on the car so far, seems early for an issue like this.

 

[GmcJing]

At the dealer now, the code came up as high voltage on the DEF tank temp sensor.
The whole time we were driving, regen wasnt happening due to the code so they are attempting to bypass the code and allow it to regen again and see if that clears it up so we can finish our trip.

 

[Capsaicin]

Was the DEF tank filled?

 

[GmcJing]

Was the DEF tank filled?

Yes, just had it serviced two days before and DEF was topped up.

 

[GmcJing]

Dealer was able to fix the issue with a "software update". They didnt get any more specific about it other than that but the tech seemed to have seen this issue before on low mile 3.0's. Another 2 hours down and nothing popped up, so I'm relieved we arent stuck waiting on a part or worse.

 

[booyaltz]

I have a 2022 Diesel Tahoe RST with about 3000 miles and I just got this error. Hoping it's a quick fix.

 

[GmcJing]

I have a 2022 Diesel Tahoe RST with about 3000 miles and I just got this error. Hoping it's a quick fix.

Good luck, I hope yours is as simple as mine was. We drove another 4 hours today and all is good.

 

[Stbentoak]

It wouldn't be surprising that some vehicles may need an update on DEF dosing or algorithms. One of my other vehicles needed the same thing and never had a problem since...

 

[booyaltz]

Mine turned out to be a simple disconnected air hose somewhere near the MAF. Not sure how on earth it would just disconnect.

 

[CTown Duramax]

High output, low fuel consumption, turbo driveability, clean running, all these demands must make for a complicated system. There is some trade off, but these engines are better than ever. The old stuff had problems too.