Update on my situation: I dropped the vehicle off at the local dealer's shop yesterday morning and the tech began testing in early afternoon. The battery reportedly was "severely discharged" and took an hour and 25 minutes to bring it back to full charge, at which time he tested it on the GR8-1220 diagnostic unit. It measured 525 CCA, slightly above the minimum at which FCA will make a warranty adjustment. A copy of the test report is attached -- see the "bad-good" indicator at the bottom.
When I got home last evening, I measured the battery voltage directly across the posts at regular intervals with my Fluke 117. At 6:30 PM it was 13.07 V; at 7:00 PM it was 12.98, at 8:00 PM it was 12.96 -- then 12 hours later, at 8 AM this morning, it had only dropped to 12.85 V. So I don't understand why it would have "severely discharged" sitting for a few hours in the dealer's lot.
I've installed a pair of ham transceivers, so there was some suspicion in the shop that my "aftermarket gear" is to blame for draining/damaging the battery. However, I've measured the current draw with the radios turned off and it's only 9 mA. At that rate, it would take 4-1/2 days to deplete the battery charge by only 1 amp-hour. I make it a habit to turn the radio off when I park, but even if I forget, they automatically shut off after 30 minutes of inactivity. (By the way, this standby current isn't much more than a lighter-plug cell phone charger, which measures about 5-6 mA.)
I noticed on the drive home that the battery voltage stayed right at 14.0 V except (of course) during the stop/start cycles. This is less than the usual 14.3-14.4 reading I've noted in the past couple of months. However, before last October's overheating incident, it was usually 14.6 V, so I still wonder if the factory had it set too high, causing the initial overheating.
Tomorrow afternoon, I leave for a 1200+ mile roundtrip to Ohio, so I asked the dealer's service consultant (who has seen my recent video) what to do if the battery overheats and begins venting again. Should I just keep driving? His advice was to find a dealer in that area as soon as possible, but based on my experience so far, I'm not sure that will help -- I've already taken it twice to dealers who are unable to make a warranty adjustment due to FCA policy.
If anyone from FCA has advice, please let me know. My dealer is concerned about the situation, but his hands are tied as long as the battery continues to pass the CCA test.
Well that sucks. Big time.
I understand their position with the guidelines they have, and it sounds like they are really trying here.
To be honest, I don't think your battery will last very long, so it's just matter of time. Problem with these batteries is that they don't seem to give much warning before they go (quite a few reports on this here on the forum), so you will likely find a dead battery some day without any heads up from the sensors.
I'm pretty sure 14.6 - 14.7V is too high for the KL. Max number I've seen on mine - and seen here on the forum from others - is 14.4V.
My battery is very healthy (I think...) ; I do mostly small city / rural road driving, short stints, and the voltage reading I have all the time is 14.2V. I've seen 14V on the highway after driving for a while, but never below (or I just don't remember). And 14-14.2V is quite normal for our charging system. When it goes above 14.2V, ESS usually refuses to engage (battery charging message).
I've noticed over time that when voltage drops below 14V while charging - on a regular basis - it's a sign the battery is slowly failing. Anything above factory max charging voltage (I believe it's 14.4V in ours) is a sign of overcharging. Overcharging kills batteries.
I still think yours was overcharging for a while, until you got those flashes, and the battery took a hit.
Guess all you can do now is keep a close eye on things...