I think 12V battery died

[rzanzerkia]

P. M. preventive maintenance on the overall, is generally cheaper, less annoying, and less time consuming. Nothing lasts forever and I will never understand why waiting until something fails is preferable to replacing parts at a reasonable timeframe. On ICE vehicles there's, belts, battery, oil, fluids, sparkplugs etc. on EV's, a 12v battery every three years is about the extent of it. There are numerous posts that have demonstrated that it's a reasonably prudent idea to replace the 12v at three years on the Mach E

Now that I have learned this lesson hard way I am sure to change battery every 3 years. However locking up the car (even with jump start from other car ) is not cool.

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[rzanzerkia]

You’ve been on the forum since 2021. Surely you knew you were tempting fate with the 12VB at 4 years. I would go grab a battery at the dealer, should be about $135, grab some tools and go change it out wherever it is. Or your dealer may be able to send a technician to where it is stranded if you want to pay them for the install. Many dealers have traveling technicians.

Unfortunately I wasn’t paying attention to 3 year mark…still bad design of no warning and just not letting you put in D (even with jump cables). Gas car I would jump start and change the battery myself.
I debated changing the battery myself but in this cold weather and so many warnings despite jump cable use had me wonder if there was more to it than just the battery. Luckily I have premium care so two should be covered. Next 3 years going to upgrade better battery myself…

 

[Mach-Lee]

Unfortunately I wasn’t paying attention to 3 year mark…still bad design of no warning and just not letting you put in D (even with jump cables). Gas car I would jump start and change the battery myself.
I debated changing the battery myself but in this cold weather and so many warnings despite jump cable use had me wonder if there was more to it than just the battery. Luckily I have premium care so two should be covered. Next 3 years going to upgrade better battery myself…

FYI the extended warranty does NOT cover the 12V battery. It has a 3-year factory warranty only.

The replacement 12V battery comes with a 3-year warranty (if purchased from a Ford dealer). But that secondary part warranty is tied to the battery, not the vehicle.

In summary, if you are on year 4 of the original battery, there is no warranty coverage on it, even if you have an extended warranty.

However, you said you jumped it with cables without success, so I believe you have something else going on, and a dealer should look at it. Probably not just the 12V battery.

 

[rzanzerkia]

FYI the extended warranty does NOT cover the 12V battery. It has a 3-year factory warranty only.

The replacement 12V battery comes with a 3-year warranty (if purchased from a Ford dealer). But that secondary part warranty is tied to the battery, not the vehicle.

In summary, if you are on year 4 of the original battery, there is no warranty coverage on it, even if you have an extended warranty.

However, you said you jumped it with cables without success, so I believe you have something else going on, and a dealer should look at it. Probably not just the 12V battery.

Thanks, I understand 12V is not covered in warranty.

I am glad at least tow will be covered this time. I also suspect something else because even tow guy used his jump pack without success. Though he may not have the override feature. Ford account here reached out to me so I’m hoping they will get to bottom of this.

 

[JimmyMachE]

Now that I have learned this lesson hard way I am sure to change battery every 3 years. However locking up the car (even with jump start from other car ) is not cool.

You have a dashcam, how often did you use it in parking mode in the past 3 years?

https://www.macheforum.com/site/threads/rexing-v55-dashcam-stays-on.26845/

 

[Maquis]

However, you said you jumped it with cables without success, so I believe you have something else going on, and a dealer should look at it. Probably not just the 12V battery.

When my 12V died, it died hard. I could start the car with a jump pack, but when I removed the pack, I started getting errors (don’t recall the specifics). I didn’t try to drive it in that state.

 

[Mach1E]

I even tried jump cables for 20 min, no luck.

Were you connecting directly to the battery or to the cables on the bumper?

The battery doesn’t charge from the cables on the bumper. That’s just to open the hood.

 

[Adventureboy]

I just installed the 5th 12VB in my daughter‘s 2019 Honda last night.

Wow! That's brutal! Is it a problem with the model, or driving style, like lots of short drives/start/stops?
I killed my first Lightning battery with driveway shuffles in just over a year.

 

[Adventureboy]

@rzanzerkia Did you get this fixed up? What was the solution?

I'm thinking since the 12v battery wouldn't take a jump, it might have a shorted cell. In this case, if the DC/DC charger senses that it can't get the voltage to a certain level in a given amount of time, with a given amount of power, it is right for the car to shut down in this situation. It can be dangerous to pump power into a battery with a shorted cell (risk of fire, explosion, leakage, etc.). Perhaps it simply knows more about the situation than we do.

 

[Vgkfan]

Unfortunately I wasn’t paying attention to 3 year mark…still bad design of no warning and just not letting you put in D (even with jump cables). Gas car I would jump start and change the battery myself.
I debated changing the battery myself but in this cold weather and so many warnings despite jump cable use had me wonder if there was more to it than just the battery. Luckily I have premium care so two should be covered. Next 3 years going to upgrade better battery myself…

“As of June 2025, Ford has enabled a "Check 12-Volt Battery" notification in the FordPass app.” It worked for me a few months ago, I received the warning on ford pass and replaced the battery. It was around the 3 year mark. It seems maybe it’s not working for everyone.

 

[Sikkun]

Only thing I have ever learned about car 12v batteries is if I have to jump it and the auto shop says it “test fine”. Replace it because I’ll be jumping it again soon.

 

[RodHower]

“As of June 2025, Ford has enabled a "Check 12-Volt Battery" notification in the FordPass app.” It worked for me a few months ago, I received the warning on ford pass and replaced the battery. It was around the 3 year mark. It seems maybe it’s not working for everyone.

Does it just send an alert when there is an issue with the 12V battery? I don't see anything in the app that shows voltage of the 12V battery or status.

 

[Vgkfan]

Does it just send an alert when there is an issue with the 12V battery? I don't see anything in the app that shows voltage of the 12V battery or status.

Right, just an alert when it begins to get weak I believe. You used to be able to see the 12v % on the account site, but they “fixed” it so it would show the main battery % again.

 

[RodHower]

Right, just an alert when it begins to get weak I believe. You used to be able to see the 12v % on the account site, but they “fixed” it so it would show the main battery % again.

I wonder if my OBDlink MX+ would show 12V battery reading?

 

[Adventureboy]

I wonder if my OBDlink MX+ would show 12V battery reading?

I think it only shows voltage. There is a capacity number that the BMS either tracks or calculates, but I haven't seen it posted yet anywhere.

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