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P12A6 No start

Atlas
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Atlas Senior Enthusiast

Atlas

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Posted (edited)

2020 Silverado...5.3...4,300 miles on it. Drove to Home Depot, shut it off, bought something inside the store, returned to the truck, and it wouldn't start. It would crank for a few seconds and barely run, and then shut off. One last try before calling GM roadside to have them pick it up, and it sputtered for a few seconds and then went into a really choppy idle, and then smoothed out.

 

Now it starts/runs fine but it has DTC P12A6 and the CEL is lit up. I'll get an appointment, but I'm guessing without an actual issue, the dealer's just going to tell me they can't replicate it? What do you all think I'm looking at here? Not happy with this truck...I'm going to have them attempt to fix the leaking rear window at the same time, and there's a problem with the keyless module...damn thing keeps honking at me even though the key is IN the truck with me when I get in, and it leaves with me when I get out, and I have the alert turned off.... 

Edited by NorthskyblueT1
GMCustomerService Senior Enthusiast

GMCustomerService

Posted
Posted
14 hours ago, NorthskyblueT1 said:

2020 Silverado...5.3...4,300 miles on it. Drove to Home Depot, shut it off, bought something inside the store, returned to the truck, and it wouldn't start. It would crank for a few seconds and barely run, and then shut off. One last try before calling GM roadside to have them pick it up, and it sputtered for a few seconds and then went into a really choppy idle, and then smoothed out.

 

Now it starts/runs fine but it has DTC P12A6 and the CEL is lit up. I'll get an appointment, but I'm guessing without an actual issue, the dealer's just going to tell me they can't replicate it? What do you all think I'm looking at here? Not happy with this truck...I'm going to have them attempt to fix the leaking rear window at the same time, and there's a problem with the keyless module...damn thing keeps honking at me even though the key is IN the truck with me when I get in, and it leaves with me when I get out, and I have the alert turned off.... 

This is certainly not what we like to hear, NorthskyblueT1.  Please know, customer satisfaction is extremely important to us. Our team would be more than happy to take a closer look into the concerns with your 2020 Silverado. To do so, please send an email to [email protected] with ATTN: NorthskyblueT1/GM Trucks in the subject line.

Please include your contact information, VIN, a brief description of your concern, and the name of your preferred dealership. We look forward to hearing from you. To learn more about GM’s privacy policy, please visit https://www.gm.com/privacy-statement.html.
 
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Silverado4x4 Senior Enthusiast

Silverado4x4

Posted
Posted
15 hours ago, NorthskyblueT1 said:

2020 Silverado...5.3...4,300 miles on it. Drove to Home Depot, shut it off, bought something inside the store, returned to the truck, and it wouldn't start. It would crank for a few seconds and barely run, and then shut off. One last try before calling GM roadside to have them pick it up, and it sputtered for a few seconds and then went into a really choppy idle, and then smoothed out.

 

Now it starts/runs fine but it has DTC P12A6 and the CEL is lit up. I'll get an appointment, but I'm guessing without an actual issue, the dealer's just going to tell me they can't replicate it? What do you all think I'm looking at here? Not happy with this truck...I'm going to have them attempt to fix the leaking rear window at the same time, and there's a problem with the keyless module...damn thing keeps honking at me even though the key is IN the truck with me when I get in, and it leaves with me when I get out, and I have the alert turned off.... 

20-NA-218 1..5 (nhtsa.gov)

Atlas Senior Enthusiast

Atlas

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Posted

Thanks all, and thanks @GMCustomerServicefor offering to help.

 

I suspect it could be related to the TSB posted above for the fuel pump module/driver. I called the local dealer and earliest they can get me in in Wednesday this week. They're going to have a look at the leaking rear window and problems with the passive keyless entry as well.

 

Until then, the truck is out of service. The dealer said they didn't have any loaner vehicles available and needed to do a diagnosis before any of this is determined to be under warranty. Sigh. This will be my... (counts on two hands:) One, two, three, four, five, SIXTH! brand new vehicle I've purchased from Chevrolet since 2009, but that doesn't matter, every time, get in line! Hope to goodness it starts on Wednesday so I can get it down to the dealer.

 

Atlas Senior Enthusiast

Atlas

Posted
  • Author
Posted (edited)

Dropped the truck off this morning and I'm already in a bad mood.

 

Service writer told me that unless it's *actually not starting* as in - right now - they probably won't be able to do anything even with the check engine light on and P12A6 code set. But they'll be sure to call in a few hours and let me know.

 

I had to explain the key fob issues again and the guy just looked at me like I was stupid. I have low confidence that's getting fixed.

 

What's next? the window isn't leaking enough in order for it to deserve to be fixed?

 

No loaner vehicle, truck has been out of service since Sunday, everything "should" be covered under warranty. This little runaround jig that GM's dealers do is getting really old

Edited by NorthskyblueT1
Atlas Senior Enthusiast

Atlas

Posted
  • Author
Posted

The dealer has had the truck all day after a schedule 0730 drop off, and didn't provide me an update until 4:30 this afternoon.

 

They completed a software update (which I assume was the TSB mentioned above). According to whomever was giving me an update (not the tech), they "didn't have time" to look at the leaking rear window today, and said they didn't encounter any problems with the truck h-h-honking at them while moving it around the service facility. I have a hard time believing a software update took any more than about 2 hours to complete, from pulling the truck into the service bay, to starting it to test the changes.

 

I guess they're going to look at the window tomorrow? Didn't have time to throw some water on it today, so sure, keep the vehicle another day when a guy needs his truck back and has things to do...it's going to rain buckets on Friday, so if they could hurry the heck up that would be great.

 

@GMCustomerService, this is how every visit is supposed to go, right? Just normal life in the modern era?

 

 

 

Atlas Senior Enthusiast

Atlas

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  • Author
Posted

Alright, let's close this one out. The dealer took two full days, 7:30am the first day (which was actually the appointment time, they even asked if I was going to wait around while they diagnosed it) and had it until 5pm the second day when they were snapping it back together, to complete *checks RO* ...2.5 hours of labor by the book.

 

They did TSB 20-NA-218 for the no-start issue and then decided they needed to "road test" the vehicle for 8 miles.

 

They did TSB NA-18-383 for the leaking rear window and gave it back to me with the seam sealer freshly applied, still wet, and told me to keep it out of the rain. It was beginning to rain.

 

They spelled my name wrong, wouldn't take my calls today (they randomly called me at 5pm to tell me their tech was just finishing up), and gave me the truck back with the rear window all covered in stuff, unwashed. This is a small town dealer and they clearly suck. I hope they send me a survey :)

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