400mi 2020 Silverado RST Duramax DEAD

[FrankK986]

At least, I think the batter is dead. Woke up this morning to auto start via the remote and, nothing. Tried the other remote and nothing. OnStar wouldn’t connect and keyless entry buttons on door don’t work.

 

It’s 11* here in Boston. Luckily I was home and drove another vehicle. Heading back home to inspect.

 

Last time i drove it was Thursday.

 

Only thing I can think of if that i installed LED’s for the front turn signals. Would these draw phantom power...and enough over 30 hrs to kill the battery?

 

 

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[FrankK986]

UPDATE. Requested tow to dealer via OnStar app. Finally got it running after using combo battery pack and jumper cables. Battery was complete dead.

Truck threw a bunch of codes and received three diagnostic errors emailed from OnStar. Had it towed to dealer.

Truck has 402mi on it. Checking the app it now shows DEF is low but service advisor says it might clear itself up after they hook it up to GM computer.

May have it back Monday. They said they may have to replace the battery. Will provide update.




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[Colossus]

Hopefully it is something as simple as a defective battery and that solves the rest of your issues.  I'm going to suggest people purchase good jump packs and keep them maintained and in their new trucks going forward. 

[ILSilverado]

Oh Dear please keep us informed as to what’s going on. Just turned 200 miles on my Duramax.

[TJMCODE]

I found my 2020 DURAMAX DIESEL RST dead this morning also. Less than 300 miles on the truck. We all can't have defective batteries!

 

Had your truck been in lately for the Remote Start / ABS Recall?

[CMT1]

I have a 2020 AT4 with 5.3 V8 with 1800 miles. Did not drive for three days and went to start and truck was dead. Battery was at 3 volts.  Charged all night. Took into dealer next morning.  They did the break/ app recall service and said maybe you left a door ajar or something that drained the battery . Not feeling real confident that it want happen again. Luckily  it was in garage at home. I live in S Texas so cold environment is not an issue.

[bshort]

I leave mine sitting for up to 14 days at a time.  No issues.  

[TJMCODE]

After finding mine dead on Sunday I did a deep charge...  took 4 hours to complete.

 

NOTE: The Auto-Start/Stop Trucks have AGM Batteries and you must use an 'intelligent charger' to avoid damaging them.

 

They held a charge the 1st two days (~12.9V DC) but this morning--after not driving since Sunday--they have dropped to ~12.3V DC, doesn't seem right.

I'm in 'Stay at Home' mode in Michigan so I'll check it again tomorrow morning and repor tback here.

 

Question: To anyone who knows...

 

Do the DURAMAX 3.0L Trucks have two (2) batteries like the V-8 Diesels?

The Owner's Manual is not clear and the Battery(s) are hidden in an enclosure with remote posts.

 

 

[HondaHawkGT]

Defective batteries has been a common issue with AGM batteries these days. Between all the auto-start/stop and electric steering stuff, they get put under a ton of stress. I wouldn't be surprised if the engine bay gets insanely hot when the engine does a regen. Is the battery wrapped in insulation to shield it from heat? If not, I would try to cover it up with battery insulation and heat reflective material.

[Colossus]

AGMs don't handle moderate discharging and recharging very well.  I'm surprised GM chose to go this route. 

[Colossus]

Then again, no I'm not.  GM has really done a lot of stupid things over the past 10 years. 

[topgear1224]

After finding mine dead on Sunday I did a deep charge...  took 4 hours to complete.
 
NOTE: The Auto-Start/Stop Trucks have AGM Batteries and you must use an 'intelligent charger' to avoid damaging them.
 
They held a charge the 1st two days (~12.9V DC) but this morning--after not driving since Sunday--they have dropped to ~12.3V DC, doesn't seem right.
I'm in 'Stay at Home' mode in Michigan so I'll check it again tomorrow morning and repor tback here.
 
Question: To anyone who knows...
 
Do the DURAMAX 3.0L Trucks have two (2) batteries like the V-8 Diesels?
The Owner's Manual is not clear and the Battery(s) are hidden in an enclosure with remote posts.
 
 

Now it's a single battery with a 220 amp alternator.

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[topgear1224]

Now it's a single battery with a 220 amp alternator.

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if you're looking for jump packs just avoid all of the lithium ones.

lithium batteries can provide a ton of power for 5 to 10 seconds and on a diesel with glow plugs that's not enough time to actually start the engine and once you go past that 5 to 10 seconds you're looking at maybe 30 amps coming out of the lithium pack. (Winter would be the concern here.)

Lead acid jump packs are much heavier but they can actually give you their rated cranking amps for 30 seconds.

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[mattmcclellan]

2020 Chevy 2500 HD Diesel. California.

170 miles.

 

Bought it last night, it sat outside overnight for 8 hours and went to use the key fob and NOTHING, the brakes were even locked up. Had it towed to the local dealership, but they said everything checked out ok. b

[markhunt]

I have a 2020 GMC 2500HD 6.6 and have had it towed to dealer twice in the past 2 months with totally dead batteries. they could not find any problems. Scary.