I have a few questions about the ESS (automatic stop start) and the battery that it uses.

I have a 2018 Pacifica minivan (Touring Plus) that has been idle for most of the last 15 months or so. It was started about every other month, except for maybe the last 5 or so. When I started it up last week, there was minor hesitation, but it started without any issue. When I'm driving, the battery info screen on the dash says the battery voltage is between 13.6V and 14.2V. The car starts normally now, and remote start works fine when I remember to put gas in it.

Now for my question. The ESS is not working. When I go to the info screen for the ESS, it says it's not ready and that the battery is charging. I believe I have read that the ESS uses the auxiliary battery. I have put a few hundred miles on the vehicle in the last week, and the ESS screen still says battery charging. Will the alternator charge the auxiliary battery eventually? Is that battery dead? Are there are other systems besides the ESS that use the auxiliary battery?

(I posted this same question on the other Pacifica forum)

 

did you observe this when you purchased the vehicle? Was this always the case? Could it be because the vehicle is in use (running) this battery is always in "a state of recharging"? Take it to your local dealership and ask the same question - they should be the subject matter experts. Sorry I couldn't help you with your question

 

When I purchased the van, the ESS worked normally, and it worked correctly up until I noticed it this week. I would rather have teeth pulled then go back to the dealership. Another forum suggested that my aux battery is likely dead, while the primary battery is okay. They recommended replacing the auxiliary battery or disconnecting the negative cable on the aux battery and not using the ESS, which is actually what I think I will be doing.

 

Might still be under warranty. You could save a hundred bucks or more if so. It's worth asking.

 

I totally understand not dealing with the "stealership". However, the aux battery may still be under warranty and could save you money. Besides, there may be other issues that may come up because the aux battery has been disconnected from the system.

BTW: Go online and see if you could purchase service and technical manuals for your vehicle. It saved me a bunch of headaches with the "stealership". I call it "Know before you go" theory. They wanted to charge me 9 hours labor on a "replace" (they DON'T repair anything because they're technicians - not mechanics). "According to the service manual", I stated, "This should have taken him 2.5 hours to do. I'm not paying for his training. That's your job. Oh yeah? Let me speak to the manager."

Works everytime.

 

I have actually been looking for a way to disable the ESS, so disconnecting the negative cable to the auxiliary battery is what I plan on doing. That battery may be dead, even if new, whenever it gets reattached. I won't be bothering the dealership for that.

 

2018 Pacifica Touring Plus 30,000 miles. I am having same problem with stop/start. Great for 2 years then 8 weeks ago issues began. Dealer replaced both batteries primary and ess battery. Started having same problem 6 weeks later yesterday they replaced the ess battery again but warning light still on and stop/start not working. I feel something must be draining this battery. All the dealer says is they replace a lot of these batteries in Pacifica’s anybody know anything about this?

 

My public library has Alldata. I would check with your nearest library to see if you can get some info to help you out. Alldata will have bulletins, service procedures, etc. Shops use it-but they have to pay for a subscription. I would find the location of the battery and test it with a multimeter, and check to see if indeed the correct battery is installed. We have had similar issue with a Ford C-Max hybrid, where after 6 months the 12v battery would be dead and couldn't be recharged above 12.30v. Yet the first battery lasted 4 years when we bought the car new. We had 2 shops (including the dealer) try to figure it out, and no answers, just theories. If I remember correctly, they can see if there is current loss at an open circuit,, or bad ground, just from their computer connected to the data port. I gave up simply just bought a cheap $5 trickle charger from Harbor Freight, and plug it in overnight every so often. And now since, the latest battery has lasted for a year.

 

Sorry for the frustration, Don. Please do not hesitate to follow up with our customer care team for further support if you need to address this any further with your dealer. You may call in at 800-247-9753 or submit your info here to receive an email follow up. https://www.chrysler.com/webselfserv...EmailPage.html.

Mark
ChryslerCares

 

Both batteries went bad and it's only been 3 years. I've just replaced both batteries, and now I'm getting an error message that batteries are charging, start and stop function not available. It's clearly a wiring or software issue, as I've seen it multiple times over the internet. It's been since 2018, this stuff should all be worked out by now.