Brand new Sierra - Codes P25A2 - U0101/100/146

[Dalton Delogu]

Just picked up a brand new 2019 elevation model. Just hit 1000kms and did my first full tank of gas. 
 

was installing a new tonneau cover at night and had the bed lights turned on for maybe 20 minutes. Went back in to drive and engine light was on with these codes. 
 

reading about brake failures and stuff isn’t very re assuring. Called Gm and send me these codes. 

many info on these or what it could be ? Truck runs fine. 

 

[brianf60]

There is another thread going on this.

 

[whitesierraRT]

I'm receiving these exact same codes on a new 2020. Had it in the shop twice because the battery would drain. Problem seem to start right after the recall upgrade for brake problems when starting engine remotely for which I never did. After the dealer installed a new battery and supposedly found a lose wire I took it home. It's still giving the P25A2 code and draining battery.

I'm now staying home because of Corona.

[TJMCODE]

I just got my new 2020 Silverado back from a dealer, they did the Brake / App recall (while installing the GM 2" Lift Kit) and now my battery is draining... Found the truck completely dead this morning.

[TJMCODE]

[GMC 2018]

Im a service advisor for chevrolet from my experience when you have low voltage you will get a slew of erroneous eng codes b/c of low volts as for the batt going dead that can be a few things bad ground, dead cell open circuit..... personally i think its the way they have the fuel prime pump set-up to start when you open the door. i dont know why they do it like this. i feel like everytime i walk by one you can hear it buzzing lol.

Dear RYAN MCGRATH, Here are the results of your recent On-Demand Diagnostic request on your 2020 GMC Sierra Crew Cab.   Module Diagnostic Code Diagnostic Information Recommended Action ECM - Engine System P25A2 The Engine and Transmission System is not performing as expected. An issue has been detected in the Engine Electrical System, including the Charging and Starting System that monitors and controls the engine starting system and 12V battery charging system. If the charge system light stays on, or comes on while driving, there may be a problem with the electrical charging system. Driving while this light is on could drain the battery. If a short distance must be driven with the light on, be sure to turn off all accessories, such as the radio and air conditioner. Service within 7 days SDM - Airbag System None No Error Code Found None VIU - OnStar System None No Error Code Found None TCM - Transmission System None No Error Code Found None BOI - Bulb Outage Indicators None No Error Code Found None ABS - Braking and Stability System U0100 An issue has been detected in the Antilock Brake System. No action needed ABS - Braking and Stability System U0101 An issue has been detected in the Antilock Brake System. Service within 7 days ABS - Braking and Stability System U0146 IGNORE UNKNOWN DTC No action needed

[whitesierraRT]

Update - Truck seems to be functioning ok now. However when I check engine codes with my code reader the P25A2 still comes up even though the engine light is off. I tried to clear the code with my AUTEL reader without success. Any suggestions to clearing the code? Not going to the dealer right now because of the virus thing. 2020 Sierra 3 liter Duramax.

[paulny]

My 2020 is just 3 weeks old, and only has 836 miles on it when the check engine light came on today after I picked it up from an auto detailer.  He uses a pressure sprayer before washing the vehicle, but am not sure if that matters.  The check engine light was not on before I dropped it off to him earlier this morning.  Yet, after picking it up this evening, it was and still is on.  Any ideas?  Can I take it to an Autozone or Advance Auto to get a code reader to give me the code?

 

Edit:  This morning the code did not come on when I started the truck or drove it.  A friend has a scanner and pulled the P25A2 code which was stored and then he cleared it.  Any reason to worry as it seems it was a temporary glitch?

Edited March 27, 2020 by paulny

[Brizzo Jenkins]

I have a 2019 Silverado WT double cab with 4800 miles. All recalls up to date. This morning it was cold so I warmed up my truck for about 10 minutes.  When I returned, I found a check engine light on the dash. I drove to work (about 15 miles).  Truck ran great. No issues. Hooked up scan tool at work and found trouble codes U0146, U0100, U0101, and P25A2. Since some of the codes seemed to be EMC/computer connection issues, I opened the hood and checked all wiring harness connections. Physically pressing on each one. I then removed the passenger side door fuse access trim piece and pressed on the main wiring connection for the fuse panel.  I found nothing weird. However, when I got back in the truck and restarted it, the check engine light was gone (coincidental?) I then cleared the codes with my scan tool.  So far they haven’t returned.  But I have that weird feeling that this gremlin will be back.  Definitely seems like a possible software issue since there are so many “ECM” codes.  Unless the main computer is shot. (Highly Unlikely, as the vehicle still runs and operates normally). Does anyone have any dealer experience with this issue?

[Rocky Mountain At4]

On 4/16/2020 at 9:03 AM, Brizzo Jenkins said:

I have a 2019 Silverado WT double cab with 4800 miles. All recalls up to date. This morning it was cold so I warmed up my truck for about 10 minutes.  When I returned, I found a check engine light on the dash. I drove to work (about 15 miles).  Truck ran great. No issues. Hooked up scan tool at work and found trouble codes U0146, U0100, U0101, and P25A2. Since some of the codes seemed to be EMC/computer connection issues, I opened the hood and checked all wiring harness connections. Physically pressing on each one. I then removed the passenger side door fuse access trim piece and pressed on the main wiring connection for the fuse panel.  I found nothing weird. However, when I got back in the truck and restarted it, the check engine light was gone (coincidental?) I then cleared the codes with my scan tool.  So far they haven’t returned.  But I have that weird feeling that this gremlin will be back.  Definitely seems like a possible software issue since there are so many “ECM” codes.  Unless the main computer is shot. (Highly Unlikely, as the vehicle still runs and operates normally). Does anyone have any dealer experience with this issue?

I also have these four codes and the CEL. It just came on today upon start up. My 2020 Sierra 1500 At4 only has 500 miles on it. The dealer said there is an update available for the braking system control module. Once I get it updated I will report back.

[splatmatt]

I had this issue seems to be fixed at the moment (has only been a week)

 

Dealer said they applied TSB# PIT5735a which I believe is this:

 

https://static.nhtsa.gov/odi/tsbs/2020/MC-10173676-9999.pdf

 

No error codes - I will update later this week

 

So basically the brake module is staying on (after turning vehicle off) and reading the wheel sensor. Dealer said they flashed brake module with new firmware to fix issue. The TSB dated 3/4 mentions that GM will provide an update later to correct issue. From my understanding the dealer just got this new update a few days ago. Time will tell. 

So if all of the error codes are listed under the brake module then this is your problem. In my case, the bluedriver scanner shows the truck's error codes were from the brake module.

[Rocky Mountain At4]

Well, I got my truck back after they updated the  brake control module with the new software and everything seemed good. Today I fired her up again and got an immediate check engine light. OnStar did a diagnostic report and showed that they "failed to probe" the ECM, SDM, TCM, BOI, and ABS system and could not read the check engine light codes. I will call the dealer tomorrow morning and get it back in. I was about to put a 1" front level kit on, but I am now thinking I need to hold off until they fix this issue. Anyone had success yet?

[Rocky Mountain At4]

Truck is back with the dealer and they said the previous software update was supposed to fix the problem. They have escalated this with GM and are talking with their engineers. There is no fix yet.

[Brizzo Jenkins]

I originally had the brake control module software update done 2 months ago.  (Brake pad life Remaining percentage was counting down too fast).  I got my first check engine light with codes about a week after that.  I used my scan tool and cleared the codes. 
 

but then, 2 weeks ago, I get a letter from big (corporate) Chevrolet saying that there is an issue with the brake control module software that needs to be addressed.  The letter also stated that, “even if you have already had the software update done in the past, it will need to be re-updated again.“ so I took my truck back to the dealer again, 2 days ago for the second time for this same “update”. 
 

so far so good with no check engine light or engine codes. I don’t know if the faulty software update and the engine code issue is related, but so far so good.  I’ll keep you all updated

[Rocky Mountain At4]

A quick update.  GM engineers told me my truck was safe to drive with the aforementioned codes and said they are working on a fix. That did not make me happy, but whatever.  Then today, the check engine light came on again and my transmission started going downhill fast. It started making hard, jerky shifts before it decided to shift into I would guess 3rd gear while I was doing 75 mph on the freeway.  The rpms went to about 4500 instantly. I got off the freeway a d it did not shift out of that gear for the rest of the trip. After shutting it off and driving it again about 3 hours later it was shifting with major issues.  At one point it would not advance gears and was just revving/bouncing off of one gear almost like I was hitting the rev limiter even though it was at about 3000 rpms. OnStar is showing codes P0700 and P2715 with the following description. 

 

The Engine and Transmission System is not performing as expected. An issue has been detected in the Transmission System that transfers power from the engine to the drive wheels. You may experience reduced power or shifting issues.If the vehicle is continually driven with the check engine light on, the emission controls might not work as well, the vehicle fuel economy might not be as good, and the engine might not run as smoothly. This could lead to future repairs.

 

This truck is not drivable or safe. I will be going back to the dealership for the third time. I have just over 1200 miles on it now...