DEF level sensor issue

[972sparky]

I have a 2022 and have used 2- 2 1/2 gallon jugs in just over 13,000 miles and is still showing 75% on Banks gauge. I estimate that is about a 1/2 gallon per thousand miles, no towing.

 

[GARRELL]

I have a 2022 and have used 2- 2 1/2 gallon jugs in just over 13,000 miles and is still showing 75% on Banks gauge. I estimate that is about a 1/2 gallon per thousand miles, no towing.

Ok. Thanks. Makes sense that mine at 5200 miles would only be down a little more than 2.5 gal. It did flash 7/8 ths on the guage a couple times and then back to FULL.

 

[RK58]

My sensor was reprogramed again and so far working as it should.

 

[DLAv8r]

2023. Def full at last oil change at 7k miles. It hasn't budged off full in 1500 miles since and today I got a pop up message on app and in truck that my DEF was low and to fill up. I topped it off and the app and truck hasn't reset. It is still showing full on the DIC, but giving me the warning. Taking it in today to see if they can apply the TSB related to this to fix the glitch.

 

[kerlyb]

My sensor was reprogramed again and so far working as it should.

Was reprograming same as recent GM service bulletin 22-NA-150

 

[Drusifer]

2023. Def full at last oil change at 7k miles. It hasn't budged off full in 1500 miles since and today I got a pop up message on app and in truck that my DEF was low and to fill up. I topped it off and the app and truck hasn't reset. It is still showing full on the DIC, but giving me the warning. Taking it in today to see if they can apply the TSB related to this to fix the glitch.

What was the outcome of your dealer visit? My 2022 Tahoe’s DEF gauge shows 7/8ths full but got the DIC and app message last week that DEF is low. It was full 2,000 miles ago so I assume the gauge is accurate. Dropped it off at dealer yesterday and they just called letting me know it is ready. Said all it needed was an update.

 

[Kenmotorist]

Ok. Thanks. Makes sense that mine at 5200 miles would only be down a little more than 2.5 gal. It did flash 7/8 ths on the guage a couple times and then back to FULL.

I have the same exact issue. Gauge always showed full for circa 2k miles. Not towing. One day it showed 7/8 full then went back to full Took it in for oil change couple of weeks ago. They filled up the DEF tank. Told me no issues. Been driving about 200 miles since. Gauge showing 7/8 full. Very confusing. I would rather not carry a DEF bottle around. DEF should not be exposed to direct heat/sunlight. If l get low on DEF on a trip I’ll either do the nearest GM dealer or look for a truck stop with fresh DEF.

 

[Jay P Wy]

There is a TSB for this. From GM Trucks dot com ->

Attention diesel GM truck and SUV owners! General Motors has released a crucial service bulletin addressing specific issues related to the Malfunction Indicator Lamp (MIL) and Diesel Exhaust Fluid (DEF) level sensor. If you are driving any of the affected models listed below, check out if you have any symptoms that match those covered by this TSB.

Affected Vehicles:​

All models have a 3.0L Duramax (LM2) or 6.6L Duramax (L5P) Diesel Engine:

• Cadillac Escalade Models (2021-2024)
• Chevrolet Silverado 1500, 2500HD/3500HD, and Suburban (2020-2024)
• Chevrolet Tahoe (2021-2024)
• GMC Sierra 1500, 2500HD/3500HD (2020-2024)
• GMC Yukon Models (2021-2024)
• Chevrolet Silverado 1500 LTD (Specific VINs)
• Chevrolet Silverado 1500 New (Specific VINs)
• GMC Sierra 1500 Limited (Specific VINs)
• GMC Sierra 1500 New (Specific VINs)

Symptoms:​

Owners of the affected vehicles may experience one or more of the following issues:

• Illumination of the Malfunction Indicator Lamp (MIL)
• Display of “Service Emission System” and/or “DEF Level Low” messages on the Driver Information Center (DIC)
• Incorrect DEF level sensor readings
• Erratic behavior of the DEF level sensor
• DEF level sensor getting stuck

Cause:​

GM Engineers have determined that these issues may be attributed to a software anomaly within the vehicle’s system.

Repair Procedure:​

To address these issues, it is crucial for vehicle owners to take their vehicle to an authorized GM dealer. The dealer will perform the following steps:

1. Update the K115 Reductant Control Module with the latest calibration.
2. Ensure the DEF tank level reads at least 35% in GDS2. If not, add one gallon of Diesel Exhaust Fluid to the tank and perform a Reductant Fluid Tank Level Reset using GDS2.
3. Fill the remainder of the Emission Reductant Fluid Tank with Diesel Exhaust Fluid.
4. Clear any Diagnostic Trouble Codes (DTCs) after programming is complete.
5. Please note that no parts are required for this repair, and the labor time is estimated at 0.9 hours.

TSB / Service Document Number:​

22-NA-150
Originally Issued in 2022 but reissued in October of 2023

 

[Drusifer]

What was the outcome of your dealer visit? My 2022 Tahoe’s DEF gauge shows 7/8ths full but got the DIC and app message last week that DEF is low. It was full 2,000 miles ago so I assume the gauge is accurate. Dropped it off at dealer yesterday and they just called letting me know it is ready. Said all it needed was an update.

Update on my issue. Got it back and gauge read 3/4ths. Drove a 1,200 mile trip the last couple of days. Stopped at QT 50 miles into the trip to fill up with DEF and it took 1.7 gallons, which is about a third of a tank. I would say the gauge is directionally accurate based on this. Didn’t receive any DIC or app alerts for low DEF during the trip.

 

[RK58]

Was reprograming same as recent GM service bulletin 22-NA-150

I am sorry I don't know the reprogram they installed but the first time never cured the issue so I assume they did the service bulletin you mentioned. I just did a 1300 mile trip at highway speeds and it only went down 1 bar only took 2 quarts now back reading full. With 15,000 miles on it now it has been almost flawless.