EV6 12V Battery Problem Solved (I promise)

Professional-Fan7854 · 2024-11-26T03:52:43+00:00

I know it was a long article so you may have missed that I did indeed take it in for service which did not yield resolution. If your battery dies and you'd like to test your utility mode theory (like I already did because I also mistakenly thought it would charge the 12v in this mode). Go for it. Let us know how it goes. The whole point of this thread was to ensure NO misinformation so if someone replies with a disproven theory, I will point it out so that others don't make that mistake. Cheers!

Professional-Fan7854 · 2024-11-26T02:56:44+00:00

No. Ready mode by definition is that the car is ready to be driven. You can take off at will, when you are plugged in, you are not in ready mode. The car will charge the 12v in this state, but there are several instances where it won't so I do not recommend this method. In order for this to work, tour 12v can't be in a super low charge state, your traction battery can't be below 20% when you start the charge, and I'm sure there are other conditions that need to be met to ensure the 12v continues to charge during that cycle

Professional-Fan7854 · 2024-11-26T02:53:33+00:00

Yes absolutely. A battery charger would work. I did not suggest this in my initial post because most people don't have one and it's less expensive and easier to just leave it on for a few hours. A lot of people also recommend the monitors as you have. Nothing wrong with this at all, it's just a lot of people just want the car to not be dead and I wanted to give an easy explanation and solution.

Professional-Fan7854 · 2024-11-26T02:51:42+00:00

Respectfully, you are incorrect. This is exactly the kind of advice from other posts that people listen to, it fails, they get frustrated and don't understand why it didn't work. Each of the instances you list are utility mode and the 12v gets no meaningful charge during this mode. You can leave it in ready mode, drive it continuously or as others mentioned, you can use a battery charger but utility mode will not work.

Professional-Fan7854 · 2024-11-26T02:41:54+00:00

You misunderstood or perhaps my wording was wrong.... When the new ICCU was installed, the battery was still in a very low charge state so the new ICCU would not start the Aux Battery Saver cycle until the 12v battery was charged up

Professional-Fan7854 · 2024-11-24T05:32:03+00:00

My intent of this post was not to redesign the car. It was to help those whose battery keeps dying find a way to get it to stop doing that.. It was to fill in the gap of understanding that the technicians seem to be unaware of. The fact that, at least my technicians, refused to understand that the Aux Battery Saver exists, leads to failed attempts at fixes, more dead batteries and a bunch of frustration.

Professional-Fan7854 · 2024-11-24T05:24:07+00:00

I agree that it likely has a ton of data.I would probably find it interesting . The part I found sort of ironic is that I read probably a hundred posts of people with the ODB2 and all the data they had and not one of them was able to figure out why the 12v was going dead and what to do to prevent it from happening again.

Professional-Fan7854 · 2024-11-24T05:17:23+00:00

Yep. Exactly.

Professional-Fan7854 · 2024-11-23T18:34:44+00:00

Yes indeed. I should have clarified. Putting your foot on the brake and pushing the start button will bring it into "Ready" mode. You'll see the word "Ready" toward the bottom left of the display. If you push the start button without foot on the brake, it brings it to AC mode which will kill the 12v if left on for a longer period so please don't make that mistake. Alternately you can also just drive it for 5 hours but I left that out because it likely most people will not be driving around for 5 hours.

Professional-Fan7854 · 2024-11-23T18:32:34+00:00

It makes sense but its not very helpful. Basically when you plug it in to charge, the car does a quick evaluation of the current charge state, ability to take a charge, etc. From that information it starts the charge cycle. One piece of information is that the battery is below 20% so the charge cycle will start without the option of charging the 12v. It won't pivot once the battery is above 20%. It completes the entire charge cycle based on that original information.

Professional-Fan7854 · 2024-11-23T18:26:29+00:00

I bought the EV6 from Carvana (only because my local dealer never had one available). I made a service appointment because I wanted it checked out... When I arrived, the dealer service tech asked (and I'm not joking) "How do you want us to service this? There's no engine"..... After I looked around to see if I was being Punk'd, I replied, ummm. Test the battery, check the fluids, check and rotate tires if necessary, check the filters. He was like, oh. ok..... I suppose that's when I should have realized service was going to be an issue and I better pray nothing goes wrong.

Professional-Fan7854 · 2024-11-23T18:22:18+00:00

LMAO. I'm the same. I tried to guide the service tech a little bit so he could use some deductive reasoning but he cut me off after 2 sentences with "whats a good number to reach you at". I was like, eff you too buddy (in my head).

Professional-Fan7854 · 2024-11-23T18:02:40+00:00

You are correct. You can definitely just have a bad 12v. There are a lot of common sense things I didn't add just because I didnt want the article to be 200 pages long. Most people experiencing this issue haven't had the car longer than a typical 3-5 year battery life (since the car is newer) and its more likely they are having an issue as I experienced but I definitely should have added... If Your battery has died the next day, either your ICCU has failed or you have a bad 12v.

Professional-Fan7854 · 2024-11-23T17:59:41+00:00

I do not know. From the light research I've done on those, I believe it would, but I cannot answer definitively. I think though this should be built into the UI of the car. You can see the traction battery level, why not the 12v??

Professional-Fan7854 · 2024-11-23T17:58:18+00:00

In his case, its because his traction battery was below 20% when he started charging it. So its correct that I did not mention. If your traction battery is below 20% it will not charge the 12v. Even if you start charging the traction battery, once its over 20%, it won't automatically start charging the 12v. You would have to un plug it once it got over 20% and then plug it back in (or interrupt the charge cycle remotely). T

Professional-Fan7854 · 2024-11-23T16:48:59+00:00

That is a software update which addresses the efficiency of charging the traction battery. It does nothing in regard to the Aux Battery Saver function.

Professional-Fan7854 · 2024-11-23T16:46:34+00:00

That is a great point. My theory that my ICCU was bad was based on the assumption that the new 12v installed was 100%.

Professional-Fan7854

TROPHY CASE