Trouble light after charging

[Marktime]

This is the 3rd or 4th time this has happened. After leaving the car on the charger for 2 days, I will get a trouble light on the dash. It goes away after a few days and if I have onstar run a diagnostic, they can't find a problem.

 

[cwerdna]

What EVSE are you using?

 

[Marktime]

Bosch but I had it happen once on a ccs too

 

[NORTON]

If your 'check engine light' is on, Onstar should be able to read the code.

I recently got the light and had Onstar read me the fault name and gave me the code number. I don't have it handy now, but it has something to do with a short glitch in the grid power.
And it does go away on it's own after 2 or 3 complete charge cycles. This sounds like what you had.

 

[Marktime]

Thanks. That does sound like it.

 

[Nashco]

As mentioned, if the power goes out or gets interrupted unexpectedly (as seen by the vehicle) it will leave an idiot light on the dash. It's unfortunate that it doesn't give you any information about the diagnostic code, but I've become familiar because of how the crummy OpConnect EVSE at work operates.

If you want more information and don't want to be at the mercy of OnStar in the future, this is a very handy device:

http://www.amazon.com/LELink-Bluetooth-Energy-OBD-II-Diagnostic/dp/B00QJRYMFC

I've used a couple of apps with it (on my iPhone 6), and OBD Fusion seems to be the best for checking codes so far.

Bryce