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Posted

I bought a 2020 1500 GMC Sierra in October of 2020. Four or five times after sitting for four or five days I needed to boost it to get it to start. 
The truck would do absolutely nothing and after boosting for a couple minutes would turn over and fire up like there was nothing wrong. The first couple times I thought I must have left something on, but began to question it after that. After this happened a few more times, I called the dealership where I bought it and they told me this was normal!!!

I was told that the trucks need so much power to keep the system going, that I needed to start the truck every couple days or so. If I let it set for a week in the summer it will not start. This winter if I let it set for two days, I have to boost it on the third day. 
I live in Maine, so I know it’s cold outside. 
But I have never heard of this issue with any other make or model. 
Has anyone had a similar issue?

Posted

Let someone test the starting/Charging system, Load test battery and perform a parasitic draw test. 

Posted

i would try a different dealer, there is  NO way thats a normal condition. what do they do at the large dealers? drive 50 trucks once a week? if you get no satisfaction go to GM regional and on up the ladder. squeeky wheel gets the grease!

  • Like 1
Posted
32 minutes ago, edebsdow said:

I bought a 2020 1500 GMC Sierra in October of 2020. Four or five times after sitting for four or five days I needed to boost it to get it to start. 
The truck would do absolutely nothing and after boosting for a couple minutes would turn over and fire up like there was nothing wrong. The first couple times I thought I must have left something on, but began to question it after that. After this happened a few more times, I called the dealership where I bought it and they told me this was normal!!!

I was told that the trucks need so much power to keep the system going, that I needed to start the truck every couple days or so. If I let it set for a week in the summer it will not start. This winter if I let it set for two days, I have to boost it on the third day. 
I live in Maine, so I know it’s cold outside. 
But I have never heard of this issue with any other make or model. 
Has anyone had a similar issue?

This is the same issue I am having with my Suburban, there is a bulletin out from GM it’s the SMCM (seat memory control module) I pick mine up tomorrow from the dealer. The first time I brought it back I accepted their reply of a not charged battery. The second time I was not allowing that answer and they dug deep and found the bulletin.

  • Like 1
Posted
1 hour ago, edebsdow said:

I bought a 2020 1500 GMC Sierra in October of 2020. Four or five times after sitting for four or five days I needed to boost it to get it to start. 
The truck would do absolutely nothing and after boosting for a couple minutes would turn over and fire up like there was nothing wrong. The first couple times I thought I must have left something on, but began to question it after that. After this happened a few more times, I called the dealership where I bought it and they told me this was normal!!!

I was told that the trucks need so much power to keep the system going, that I needed to start the truck every couple days or so. If I let it set for a week in the summer it will not start. This winter if I let it set for two days, I have to boost it on the third day. 
I live in Maine, so I know it’s cold outside. 
But I have never heard of this issue with any other make or model. 
Has anyone had a similar issue?

My Sierra 6.2L 1/2 Ton AT4 is my third vehicle (least used).  It has sat for a couple of weeks a couple of times since I bought it.  It is pretty cold here as well, never failed to start.  I would seek out a new dealer for maintenance.

Posted (edited)

I've had it happen 3 times in the last 15 years.  All 3 were GMs with original battery that went to crap when it got cold.

 

2006 Chevy Cobalt SS Supercharged

2008 Saturn Outlook

2017 Chevy Traverse

 

That's 50% of the vehicles I've owned during that timeframe.  All 6 vehicles were GMs.  My Silverado isn't included in this count.

 

I have zero faith in AC Delco batteries.  As soon as a battery craps out I replace it.  It's the one thing I'm not doing warranty repairs on.  You can get the same group battery with better ratings for CCA, CA, and reserve than the AC Delco batteries do, and they're also cheaper because they don't have the dealership markup.  I like Exide NASCAR Extreme, but that seems to be impossible to locate in my area, so I went with the platinum line of whatever AutoZone is selling for the Traverse.  On several reviews I found online it was rated pretty good and appeared on more lists than other brands I found in my area. 

Edited by Transient
Posted

I believe Auto Zones are made by Exide, they also make Die Hard and many others. I never had much luck with them or Deka. I think Interstate is the best. believe it or not WalMart batteries are pretty good bang for the buck 

Posted

My 2012 had a draw somewhere, didn't matter on the battery as it was changed twice to other brands. Never bothered to figure it out since it did drive nearly every day but the odd times is sat for a week in the winter, it died.

 

Bugged me a little that if we went on a trip or something and it was parked at a lot for over a week, I knew I was going to need a boost. 

 

Good luck, push GM to figure it out and don't let it slide like I did.

Posted

I had a 2013 Tahoe that would not crank after sitting 3 to five days, always had to jump it to start. Took it to the dealer, they diagnosed for 3 days, said they could not find the cause.  Told me it would be a daily diagnostic charge if I wanted them to continue to troubleshoot it. I gave them the "F.. off" look. Finally just traded it in.I had a 2013 Tahoe that would not crank after sitting 3 to five days, always had to jump it to start. Took it to the dealer, they diagnosed for 3 days, said they could not find the cause.  Told me it would be a daily diagnostic charge if I wanted them to continue to troubleshoot it. I gave them the "F.. off" look. Finally just traded it in.

Posted

Welcome Letsride, thats good info and likely Es problem, Hopefully he can get the dealer to cooperate without a hassle depending on where he is in Maine there may not be the option of another dealer local to him

  • 2 weeks later...
Posted

having the same issue with my 2020 2500HD Denali. First time i thought i left something on and just charged the battery. 10 days later same thing, took it to the dealer and they replaced the battery and did a parasitic test. they found nothing draining it, well a week later....dead battery. At the dealership now and i will let them know about that GM bulletin about the seat memory control module. following this thread and i will report back with my results

  • 1 month later...
Posted

OK, so one month later and GMC replaced the seat memory control module and also found the rear window had a leak, which they then sealed. They were skeptical about the SMCM but must have looked it up as well. Since the repairs, knock on wood, no issues even in the below freezing temps which is when I had the issue.

 

Big shout out to Letsride thanks!!

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