So 45,000 Miles In, My Ford Dealership Asks for $695 To Replace My Mustang Mach-E's 12v Battery, Which It Said Was Healthy at 94%

Hybrids can have the same issue.

We have a 2018 Toyota Highlander Hybrid as a fleet vehicle at work.

The 12-volt battery has now failed twice since we got the vehicle, leaving us stranded both times.

Keep in mind the vehicle is driven regularly.

Of course an ICEV can suffer the same fate.

It's a common point failure.

In 2022, Tesla replaced my Model 3's 12v lead-acid battery on when it failed after 3 years and was out of warranty.... all for about $90. Including installation... and they did it in my driveway.... I never had to leave home.

Having worked with lead acid batteries for decades at 5 years your going into borrowed time. Sedimentation and general age will cause failure sooner rather than later no matter how it tests. One or two adverse load cycles on an old cell will leave you stranded.

This article really is a nothingburger. A Ford dealership is overcharging for a 12v battery plus install - and it isn't clear if the tow charge is part of the cost listed? This is more a dealership slush bill rather than an 'EV problem'.

12v batteries go bad sometimes, whether it's an EV or an ICE vehicle. This article essentially reminds people of that. Besides, the age/mileage on this person's car seems to fit right in the sweet spot for needing a new 12v battery anyway.

This is no different than ANY other car, it is not unique to EVs.
12V lead acid batteries have to replaced every 3-5 years. And when they fail, it's generally all the same, you can't start your car.

Tesla has now moved to Lion batteries as a replacement to 12V lead acid batteries.

This article is so misleading and is obviously written by someone that does not know anything about modern automotive repair in general let alone electric vehicles. The customer's car in question is 4+ years old and is out of warranty by both time and mileage. Both things you knew when you bought it. It needs a 12V battery. Nothing to do with the fact it's an electric car. Almost all modern cars use an AGM battery that yes, needs to be replaced every 3 years or so. It's in the manual. It's on the battery. This car was towed in asking for diagnostic, not requesting a battery. So yes, that costs about $200, it's another $350 for the battery, and probably a full hour of labor again at $200 to install and program it.

You would get an F if this was submitted for ninth grade journalism assignment. No answers. Why is a 94% 12v battery level a problem? That's only question that anyone wants to know and you completely failed to answer.

This happened to my tesla. Tech came to my garage and replaced the battery for free, said the system should have warned me the battery was goin bad and apologized.

Unless that is an old vehicle that he barely drives it should be covered under the 3 yr warranty. If the batt is healthy he doesnt need to replace it, it is just what the service advisor is advising him do. Also the picture is wrong it is a small 12v boat battery.

My Advise
IMO, if under warranty have them change it out FREE before your 3 year is up.
If it is acting funny plan to get it changed out, the last thing you want is to be stranded away from home trying to open the lid, remove clips, to remove the battery to try to find a replacement as I mentioned it is a boat battery so it is not carried widely and dealers would sometimes need to order it in. I've seen people change it out for other small car batteries as you can adj the backet to hold a slightly bigger battery.

I used to own a 2015 Nissan Leaf. It would behave really weirdly when the 12V battery started failing. I knew that, and simply replaced it with a new one from an auto parts store.

What I took away from this story is NOT the exorbitant cost of the battery, but the fact that the car was inoperable after "an update."

As vehicles have become more and more reliant on computers and electronics, they've become more affected by unrelated issues with electrical components, such as an automatic transmission failing to shift because the ignition switch, which is on the same circuit, is failing.

Just wait 10-15 years and these EVs will have so many problems with all the electronics that you won't be able to give them away.

12 volt batteries don't last forever. I don't know what point you're trying to make because you have to replace the 12-volt battery in any car, not just an EV. The owner had 45,000 mi on the car. I'm guessing that was more than the 12 volt batteries lifetime. If the 12 volt battery is not covered under the manufacturer's warranty then I don't see why you're complaining that you had to buy another blood acid battery. The battery pack that is the traction battery is covered for 8 years. That is not the 12 volt battery. So I do appreciate your article stating that 12-volt batteries do not last forever but that is a fact and happens to every car not just EVS.

I understand vehicles have become more temperamental with battery charges...unlike vehicles up into the 80's that could start on a half dead battery. Toyota once told me I needed a battery in a '99 4Runner...it started/ ran fine, even in cold weather. It was 2 1/2 yrs later before showing signs (only in cold weather) that it was getting harder to start. If my vehicle is telling me the battery is at 94% health, you (the service rep) are going to need to 'hold class' in getting me to 'buy off' on replacing my 12V battery.

What an idiotic article. As if 12 volt batteries haven't been a constant problem in every gas car since the beginning of time also.

Very poor journalism: no mention of Tesla designing and implimenting 16 volt Li-ion batteries some years ago that last the life of the car - problem solved! (Driving Tesla 8 years in the Phoenix metro area)

Very poor journalism: no mention of Tesla designing and implimenting 16 volt Li-ion batteries some years ago that last the life of the car - problem solved! (Driving Tesla 8 years in the Phoenix metro area)

Well this was a real fluff article!

The MachE's 12 volt battery, like many EVs is small and it doesn't take much use to deplete it. Given the severity of the outcomes when it reaches its discharged state, it's a part that should receive extra scrutiny after an abnormal event that depletes it. Not only is gaining entry into a vehicle with a dead 12V battery cumbersome, if the battery dies in the middle of a software update, it can brick modules that are expensive to replace. Some module updates often prevent the DC to DC converter from activating during the update, preventing the 12V battery from being recharged should it get low during the update.
Did this owner really need a new battery? Hard to say. Yet, it appears to be a reasonable defensive practice that after the 12V battery is fully depleted that it gets replaced as they are not meant to be deep cycled. Lead acid batteries can have noticeable drops in capacity after being completely discharged.
I very much disagree with the dealer pricing for performing this particular replacement, yet that's the state of dealership repair pricing, unfortunately.

Should 12 volt battery use a trickle charger maintainer style charger and another charger for the drive battery it's not that big a deal! But there is a big difference in lipo charging and 12 volt charging!

Ev batteries are higher voltage like 400v. A 12v battery is what you can get at Walmart.

You had us at Mache, lol...bad purchase on your behalf, sweetheart. Internal combustion is the only Mustang, sorry.

I just had Tesla replace the 12V battery in my 2019 Model 3. Battery cost $120.00 and they came to my house and installed it for $25. Total cost $145 Canadian dollars! That's about $100 USd delivered and installed, and it is the first battery needed after 6 yrs.

My Tesla 12v battery replacement was only $138 and they sent a tech to my home and he replaced it while it was in my garage in like 10 minutes.