2021 GMC Sierra OBD status

[Amycellis]

Today I checked the OBDII status for my 2021 GMC sierra. I did NOT have a check engine light come on, however my truck has been semi-stalling and shaking, along with several other symptoms. When I press the ignition button without my foot on brake, my check engine light does not come on either.
When I scanned my truck the  status showed 0 codes yet had 3 shorter codes, 7E8, 7EA, and 7ED  listed under control module. Also, the scan status showed n/a for all three continuous monitors:

• Comprehensive Component Monitor (CCM)
• Misfire Monitor
• Fuel System Monitor

I purchased my truck brand new March 2021. Should I be concerned? Or does my truck not monitor these specific ones? Can someone please advise?

 

 

Edited July 28, 2024 by Amycellis

[CamGTP]

That truck probably has 15 different modules, not that this scanner could even read them all.

 

Many monitors either don't apply to that truck or there require specific run time for the monitor to be ran. The PCM is always running a misfire monitor even if that scanner doesn't say it is, it's always working in the background and will report an issue if there is one.

 

And fuel system monitor is super vague, what part of the fuel system is it a monitor for?? I'm not asking you that question, it's just in general because the fuel system is pretty complex on these trucks and there are lots of things that go with it.

 

I honestly wouldn't worry about it. If you have no check engine lights and you don't have emissions testings, I wouldn't care one bit.

[Gangly]

If your stumbling, there is an issue.  Since you are having three seemingly separate circuits throwing an error, I would start checking the grounds on the truck. 

[newdude]

On 7/28/2024 at 12:12 AM, Amycellis said:

Today I checked the OBDII status for my 2021 GMC sierra. I did NOT have a check engine light come on, however my truck has been semi-stalling and shaking, along with several other symptoms. When I press the ignition button without my foot on brake, my check engine light does not come on either.
When I scanned my truck the  status showed 0 codes yet had 3 shorter codes, 7E8, 7EA, and 7ED  listed under control module. Also, the scan status showed n/a for all three continuous monitors:

• Comprehensive Component Monitor (CCM)
• Misfire Monitor
• Fuel System Monitor

I purchased my truck brand new March 2021. Should I be concerned? Or does my truck not monitor these specific ones? Can someone please advise?

 

 

 

 

 

 

 

I'd advise in a better code reader.  There are a couple great bluetooth ones on the market, the BlueDriver and OBDLinkMX that can read and scan all modules on the vehicle, and then live data for engine parameters.  And they will actually give you the code, not those 3 digit "codes" yours pulled, which means your reader either can't read them or isn't able to identify the code.  

 

Readiness monitors are important only if your state does OBD emissions testing for state inspections.  

Edited July 29, 2024 by newdude