2020 3.0 Duramax - Code P2002

akawally · February 27, 2020

I bought my 2020 GMC AT4 back in early December. I took delivery up in Montana so my first drive was a 750 mile trip home. I have driven it very little since and it currently has about 1500 miles on it. I noticed the CEL on the other day so I plugged my ODB scanner into to reveal a Code P2002 Diesel Particulate Filter Efficiency Below Threshold. It was running fine, no other apparent symptoms. Read more at: https://www.obd-codes.com/p2002

I took it into the dealer two days ago. They called me later that afternoon and said that it was a new situation and that they were working with GM Engineers to determine a proper course of action but they would like to keep it overnight. I wasn't surprised, in fact I expect that out of a new power plant and I have a daily driver. Yesterday they let me know they were Fed-Exing an "exhaust pressure differential sensor" from Lansing. They said the truck was OK to drive and that I could pick it up if I wanted. I elected to wait until the repair was completed and hope to have it back today.

I didn't see this code posted on the forum so I thought I would drop this information here for others to search. I will provide another update when I get the truck back. I will also ask what this would cost if it wasn't under warranty because I think that is useful information for evaluating the total cost of owning the LM2 diesel plant. I did get an extended warranty but cost/risk and warranty coverage will be a inevitably be a huge factor in deciding how long to keep this particular rig. I really really like driving it, more than the 6.2 and ALOT more than the 5.3. I haven't towed with it yet but I hope to try that out this weekend.

WALLY

akawally · February 27, 2020

Just got an update... The sensor arrived but the technician won't have time to install it until tomorrow by EOD so I will have it for the weekend. I asked them to check for recalls and they initially confirmed that it was all up to date, but today they said that two new updates were just released so they are going to get those done also. I will find out more info on those when I pick it up.

On a side note, it seems like they have a HUGE number of T1's in for service right now, and the diesel specialists are especially highly constrained. I think TSB's and recalls have the service department running hard. Now I know where a good portion of my $61k is going.

WALLY

tlaw91 · February 27, 2020

I like your truck, nice color/option combo.

The new 3.0’s are fascinating, I can’t get over the mpgs and how quiet they are.

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akawally · February 29, 2020

On 2/27/2020 at 4:38 PM, tlaw91 said:

I like your truck, nice color/option combo.

The new 3.0’s are fascinating, I can’t get over the mpgs and how quiet they are.

Sent from my iPhone using Tapatalk

Thanks! I think its perfect

UPDATE: I picked up my truck yesterday, one of the DPF sensors was failing. The cost to diagnose and replace would have been about $800 without the warranty. I have had two of these fail on my 2016 Colorado (2.8 TD). This indicates a potential for higher maintenance for a diesel over the long term unless some delete options emerge. I got an extended (120k mile) warranty so I am not worried about it, but still just kinda interested in those costs overall. I do love this truck.

They also applied the two latest updates that were released while it was in the shop - one was for the braking system and the other was for infotainment.

Firetrout · March 2, 2020

Just had to drop mine off at dealership for Check Engine Light CODE P213A. Waiting on a call back to let me know what issue is. DIC showed 175 miles to reduced speed, service emission system. Will keep yall updated.

afterburner82 · March 3, 2020

On 2/29/2020 at 10:14 AM, akawally said:

Thanks! I think its perfect

UPDATE: I picked up my truck yesterday, one of the DPF sensors was failing. The cost to diagnose and replace would have been about $800 without the warranty. I have had two of these fail on my 2016 Colorado (2.8 TD). This indicates a potential for higher maintenance for a diesel over the long term unless some delete options emerge. I got an extended (120k mile) warranty so I am not worried about it, but still just kinda interested in those costs overall. I do love this truck.

They also applied the two latest updates that were released while it was in the shop - one was for the braking system and the other was for infotainment.

Can you elaborate on the infotainment update at all?

larryz71 · March 3, 2020

Thanks for the info firetrout & akawally. Keep us posted.

akawally · March 3, 2020

14 hours ago, afterburner82 said:

Can you elaborate on the infotainment update at all?

Yes! Here is a photo of the service sheet which specifies updates. I assumed that one was infotainment because when I picked up the truck it ejected the NAV SD card and then loaded an update before I drove it home. Looking closer it seems like the two updates were for the brake system issue and a reductant control module update which is specific to the Diesel emissions stuff.

WALLY

Firetrout · March 3, 2020

They were able to clear the code and check engine light with the redundant control mod update..............hopefully that takes care of that problem.

gone_fishing · March 4, 2020

4 hours ago, Firetrout said:

They were able to clear the code and check engine light with the redundant control mod update..............hopefully that takes care of that problem.

Thank you for the update. Hopefully this fixed your issues. Keep us posted with any other issues. I'm interested in this motor and will be in the market in the next year. BTW, what color is your Sierra and do you have any more pics? Don't think I have seen that color on the road.

Thanks!

nickchodge · August 11, 2020

I had this same problem with my 2020 AT4 3.0 diesel. Picked up in June. At 1900 miles the check engine light came on. Took it to dealer and they said the same thing: this is something new and they had to contact GM headquarters for info. I was told it was a diesel particulate sensor. They've had my truck 7 days. Am supposed to get it back today. I am in Spokane, WA.

SWBuckeye · September 4, 2020

Hi all.

I had the Brake Control Module and the ECM & Reducttant Control Module as well (3.765 miles). Then I have the exhaust back pressure valve go out and had to be replaced (code p2b97) (3,870 miles). All has been good since, at 10,445 miles now.