I just put a new engine into my 2006 Pilot. A new alternator was installed along with it. New engine runs great, but my battery warning light just came on. I went to auto parts store and they checked battery and alternator. They said alternator was fine (not surprised) but battery failed. I replaced battery and warning light is still on. I've driven it for 20 miles or so since the warning light came on, no signs of bad alternator, battery is new, what else could it be? Any advice is appreciated. I did notice a corroded engine ground strap which I plan to replace. Not sure where else to look.