If yours was a CTEK (vs the GM CTEK version), you should also had at least one other light showing state of charge.
Good suggestion. In my case, the "L" bracket hadn't changed position so it did not become an issue.08Jan21...replaced battery with recommendation from jsvette (thanks).
I installed it yesterday and took it out for a drive (short)...all good. I read that the TPMS doesn't reboot right away so I waited until today to check it.
At first door wouldn't open (keyfob in my pocket) then it did. Horn blasted...keyfob unlock...horn off. Got in and pressed start button for seating position. Moved to my seating position then all electrics turned off. I had kept the window open and used to escape manual lever. Needed key to unlock hatch.
Checked battery. Looked the same but no power.
I did remember that when I attached the +connector on the post the extended threaded post was close to the fuse/buss overlay. I attached the "L" positive bracket but it was tight, meaning not a good position.
This was the problem. I pressed near that bracket with a plastic interior tool and the power came back on. Then almost immediately off again. Then a noticed a small spark by that "L" bracket.
Removed "neg" cable and then repositioned the positive post connector and "L" bracket to a more 90degree position. Neg back on and power.
Seems to work now. Be careful of that "L" bracket.