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Onstar Transmission/Engine email

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I just received an email from Onstar for advanced diagnostics. It said:


An issue with the Engine and Transmission System in your 2019 GMC Sierra has been detected. Please service your vehicle within 7 days.”


Has anyone else gotten this email before?  I didn’t notice anything while driving it today and it seems to be driving like it always has. Also, there were no messages in the DIC and no lights were lit up on the dash. Was just curious how serious I should take this email?  Thanks in advance for any help. 

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  • 6 months later...
23 hours ago, Bill Gorley said:

I just got it to on a 2021 GMC Sierra with less than 3,000 miles on it. What does it mean??

If you don't have a check engine light I wouldn't worry about it.

When OnStar detects an issue it will throw a code then OnStar e-mails you with the code so if you don't have a check engine light or code sent to your email I would worry about it or you can hit the blue OnStar button or your mirror and tell them to run a diagnostic check

Edited by Silverado4x4
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I just had that issue yesterday in which I tried to start the truck and it immediately shuts down...repeated several times and got the same result.  Immediately afterwards I received an email from OnStar saying it detected an issue in the engine/transmission and need to get the truck serviced within a day.  As luck would have it, I noticed a check engine light on the dash.  I managed to get the truck started again and drove it home.  Earlier today I scanned the code and it stated a P12A6 that revolves around the fuel pump.  I've scheduled an appointment with the dealer to look at it and see what is req'd to resolve the issue.



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