The other day I was visiting my sister and she asked me to scan the codes on her 2014 Silverado. When I put the key in the ignition position for on (without st

The other day I was visiting my sister and she asked me to scan the codes on her 2014 Silverado. When I put the key in the ignition position for on (without starting it) so I could read the codes, it complained that the battery was low, and to start the truck soon. Oddly enough, my dad's 2001 Silverado always had the same problem (just a red battery light back then), 2 years of ownership so far and it's battery is still fine, same warning right before you start it that goes away once it's on. When I told this to her she told me her old Jimmy did the same thing. The code her truck was throwing was coincidentally the same code as my dad's 2001 truck, about the evap canister. I was flabbergasted, 13 years age difference and this truck was no different.