Thanks for the advice on charging the battery. Not sure what to make of the fact that a 2 amp charge supposedly topped it up in 5 minutes -- very, very seriously diminished battery capacity, user error (don't see how I could have screwed that up, but then again...), the battery wasn't run down to start with, or something else entirely. Regardless, I think I'm calling it quits for the night. It's going to the dealership tomorrow either under its own power or on a tow truck. Given the money involved, I'm holding out hope that it is, in fact, the battery and that the Auto Zone test result was wrong. The employee doing the test didn't even know what the word "diode" was when it appeared on her screen, so there's that. I only vaguely knew, but I don't work in an auto parts store. For anyone who's curious or for someone who comes along later with a similar problem, I'll be sure to update this thread once everything's over and done. Thanks again everyone!

 

I had the exact same issue this morning on my '15 EX with about 50k miles. I noticed it was a little slow to start on Saturday and, boom, no start this morning...but the dash lit up and it clicked when I pushed the button. I jumped it and it started fine, but I was getting the 'Check Charging System' message. We've had very rainy and humid weather here in the Boston area over the weekend, so I sort of thought it had something to do with that. I'm used to some telltale signs when a battery is starting to fade over a few months.

Anyhow, I was due for the B123 service, so I (fingers crossed) drove it about 25 miles to the dealership. It is there now...I'll keep you guys posted on the official diagnosis.

 

The dealer says my issue was the battery ($145 installed). I guess, at least where I am in the Northeast, 3-5 years is a normal lifespan for a battery...I was at 4 years. But, man, it really went from working fine to kaput without warning. I only noticed a slightly sluggish start two days ago!

 

That dinky little battery that Honda puts in at the factory is never going to have a long life.

 

 

It was the battery. Alternator is fine. Also, the free testing at Advance and Auto Zone is #%$!@#$. The former said the battery was good. It was bad. The latter said that alternator was bad. It was good. So, those of you who suspected the battery (and were skeptical that it was the alternator) were right all along.

Thanks for sharing your experience, HondaFan75. I'm relieved mine turned out to be the same. $165 for the battery was a whole lot better than $900+ for an alternator.

 

Glad you finally got to the root of the problem. Also glad it didn't cost more than it did. The dealer price was not out of line & now you won't wonder about the alternator.