Update: dealer spent 6 hours with it and said they replaced both batteries & the Shifter module. They asked that I drive it at least a 1/2 hour to further charge the battery, and noted that the stop/start service wouldn’t be ready until the small battery was 63% charged (a value you can’t see in the dash console, but you can see the status of the service which was reading “not ready”). I drove it for 30, left it on for another 30, then came back to it 8 hours later as instructed. It started & the s/s service said it still wasn’t ready. I drove it a couple of blocks, and then it said it was ready. Test time- stopped, s/s kicked in, took my foot off the brake & the s/s started it back up as designed. Then the dash indicated the service was “unavailable” (not “not ready”, but unavailable). Parked & my wife took it to work. 1/2 way there the s/s service left her briefly stranded at an intersection with the service killing the car & the “Service Shifter” error came back preventing her from shifting gears. She managed to get the car turned back on & shift it back into to drive to bring it home.
I’ve taken it to the dealer again & asked that they keep it as long as they need to to ensure we get a safe, functioning vehicle.
Hopefully the dealer will figure it out. My hunch from piecing together what others have had trouble w/ & what the dealer is telling me- I’d be willing to bet that little battery stops being charged by the bigger one when you turn off the s/s service. If you do it every time (like most people will b/c it’s a terrible “feature”), that battery gets too low to take a proper charge & it starts wearing down the main battery. If I’m right, it means we’re destined for this to be a persistent problem until/unless Chrysler changes the s/s service.
In summary- this appears to be directly caused by the Stop/Start Service, which is a part of the car even the dealer technicians & sales staff agreed everybody hates. One tech said he wouldn’t even entertain buying a car if it included the feature!!! What’s sad is how well Chrysler did with the Pacifica otherwise. This one feature stands to drive customers like me back to other brands. I’m guessing they won’t, but I’d highly recommend they just shut that feature down to course correct before guys like me revert back to a inherent distrust of the company to deliver a trust worthy vehicle.
I liked the Pacifica a lot more than the Sienna, and even felt it edged out the Odyssey in features. But if it doesn’t run, or worse- leaves the wife & kids stranded somewhere, well, these are deal breakers.