For a few days I have my battery light and "doors open" light ON at low RPM. Actually, it doesn't happen in the mornings: only in the evenings after a hot day.

I replaced battery 30K back. Alternator is new (maybe 3K back) as well. Checked the battery and alternator connection: all's OK, nothing to clean there...

The car runs fine (Accord V6 99, 98K), but I'm afraid, it may die on me one day, and that won't be fun at all...

I checked battery voltage today morning: 12.7V with engine off and 14.1V with engine at idle, so the alternator should be fine...

Could someone please advise on where I can poke next?

Thanks!