2012 LML DEF troubles

[Jmoe]

Ck engine light and Def Quality light with speed restrictions. P2Bad replaced downstream NOX sensor. Ck engine light out. Def light and speed restriction remain. I have disconnected both batteries and combined their respective leads to one another in an attempt to drain all power. Not working... Def light and restrictions remain. One maintenance shop no help. Suggestions? I also ran the engine 90 minutes at idle.

Fluid level was about one third when I first got all the indications and stopped twice and put in def to fill tank. Def in tank had been doing fine since filled earlier this year. If I can avoid driving a great distance to a GMC dealer, that would help and be appreciated. I'm new here. Thank you

 

[NC-smokinlmm]

Probably got a clogged def nozel in the exhaust.

 

[Jmoe]

Thank you. I'll report when solved by me or dealer.

 

[Jmoe]

MORE INFO ON MY 2012 GMC K3500 LML DURAMAX
EARLY DEC, 2021
ODOMETER MILES 76200

TSB'S AND GM'S SCA'S OR SPECIAL COVERAGE ADJUSTMENT program
I found this info by googling special coverage adjustment with the numbers below. Two apply to me thus far.

SPOKE WITH TABBY AT GMC 800-462-8782
SPECIAL COVERAGE ADJUSTMENT GM
When GM establishes a special coverage adjustment program that will pay for all or part of the cost of certain repairs no longer covered by
a vehicle's warranty period, they will notify dealers. When submitting a Special Coverage transaction, it is no longer necessary to select
the "special coverage" flag.

1) Special Coverage Adjustment – MIL Lamp On / Glow Plug Heater Inoperative SCA #15114

https://static.nhtsa.gov/odi/tsbs/2015/SB-10089893-2280.pdf

I had this problem repaired by my local shop NOV 17, 2020 ODOMETER MILES 68,695
NOTE: I was never advised of this SCA. I'll update after I find out if they will refund my $300 plus for the repair services.

2) Special Coverage Adjustment – Indirect Fuel Injector Replacement
SCA #14653

https://static.nhtsa.gov/odi/tsbs/2015/SB-10089949-2280.pdf

3) SPECIAL COVERAGE ADJUSTMENT DIESEL EMISSION REDUCTION FLUID TANK
SCA #14652

https://static.nhtsa.gov/odi/tsbs/2016/MC-10130605-9999.pdf

 

[2004LB7]

how many miles? have you ever had the NOX sensors replaced? most common cause for that in the early LMLs is the NOX sensors. need to replace both sensors, then reset the sensors, run a service regen and the a reductant quality test. will need a decent scan tool or the dealership to run these. codes will not reset on their own unless you can drive it at highway speeds for 30 or more miles. those codes will not clear without correcting the problem and running the tests

 

[NC-smokinlmm]

What are your actual codes set in the ecm?

 

[BigLou80]

If you are confident the issue is fixed have autozone or someone clear the codes the do a cold start followed by a drive cycle. let it idle for at least 5 minutes followed by at least 5 minutes of around town driving, followed by at least 5 minutes( and miles) of highway driving followed by some more in town driving. If the problem it fixed the derate should clear it self without perfroming a regen or a dedicated monitor cycle

How to Perform a Basic Drive Cycle

A Drive Cycle will complete the readiness monitors for your car's emissions control system. Here are step-by-step instructions to perform a basic Drive Cycle.

repairpal.com

 

[BigLou80]

If you are confident the issue is fixed buy a $15 ODB2 adapter and spend the $5 on torque to clear the codes yourself or have autozone or someone clear the codes the do a cold start followed by a drive cycle. let it idle for at least 5 minutes followed by at least 5 minutes of around town driving, followed by at least 5 minutes( and miles) of highway driving followed by some more in town driving. If the problem it fixed the derate should clear it self without perfroming a regen or a dedicated monitor cycle

How to Perform a Basic Drive Cycle

A Drive Cycle will complete the readiness monitors for your car's emissions control system. Here are step-by-step instructions to perform a basic Drive Cycle.

repairpal.com

 

[2004LB7]

If you are confident the issue is fixed have autozone or someone clear the codes the do a cold start followed by a drive cycle. let it idle for at least 5 minutes followed by at least 5 minutes of around town driving, followed by at least 5 minutes( and miles) of highway driving followed by some more in town driving. If the problem it fixed the derate should clear it self without perfroming a regen or a dedicated monitor cycle

How to Perform a Basic Drive Cycle

A Drive Cycle will complete the readiness monitors for your car's emissions control system. Here are step-by-step instructions to perform a basic Drive Cycle.

repairpal.com

DEF quality codes and reduced speeds will not clear with the readiness dive test. you either need to do a 30 or more mile drive, most report success on the highway, or an actual quality check with a scan tool

 

[BigLou80]

DEF quality codes and reduced speeds will not clear with the readiness dive test. you either need to do a 30 or more mile drive, most report success on the highway, or an actual quality check with a scan tool

I went less than 10 miles on the highway after warmup and some around town driving when the derate cleared. that being said I had a good scan tool and was able to verify the issue was resolved

 

[2004LB7]

I went less than 10 miles on the highway after warmup and some around town driving when the derate cleared. that being said I had a good scan tool and was able to verify the issue was resolved

you where still able to drive at 55 correct?