Low Voltage Battery Replacement Timeline?

[TheVirtualTim]

When do the 12 volt batteries in the Mach E charge?

The battery level is monitored. If you are _not_ driving but the car _is_ plugged in, then it will use AC power to top off the 12v battery.

If you _are_ driving and the 12v battery is low, it will use the high-voltage battery to charge the 12v battery.

This is one of the reasons why we recommend you always leave the car plugged in _even_ if it doesn't need to be charged. The car will use the AC power to maintain the 12v. It will also use that power to precondition the car for driving or if you remote-start it will use it to pre-heat or pre-cool the cabin without tapping into the high-voltage battery pack and sapping some of your range.

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[Fins160]

Expecting to replace it every two years here in AZ, just like every other car battery. The heat kills them here, not the cycles.

 

[generaltso]

If you are _not_ driving but the car _is_ plugged in, then it will use AC power to top off the 12v battery.

Only when it's actively charging.

 

[NoVAguy]

I have a question as well about the 12V battery.

If I don't charge my car for about 2-3 days, I keep getting an error message about my 12V battery being low and to plug in. This just started recently after I got stranded and got all these weird errors on the screen. The dealership said my battery was fine so not sure why all of a sudden i'm getting these errors when this had never happened before.

I've also just recently started getting these same warnings that you've described on my 2021 Job 1 Mach-E that I took delivery of in June of 2021 (roughly 2 years ago). Anytime the vehicle is left unplugged for more than 2 days or so, the battery error message comes up. I've never been stranded or had any other issues with the vehicle before this, though. Just seemed to have started out of no where.

I hope someone can answer your question as I am also interested in the cause of this.

 

[Teslaeata]

Correction to my earlier, I ignored the age-old maxim - RFM - read the frigging manual?‍

 

[TheVirtualTim]

Only when it's actively charging.

It will use the AC adapter anytime it needs to charge the 12v (so long as it is actually plugged in) ... not just when it is charging. This is something I learned back in Feb 2021 after I got the car ... there was a software bug. The engineers told me how the software was _supposed_ to work ... and then told me what it actually did (which was the bug). But that bug has long since been fixed.

I have a display inside my house that tells me anytime the car starts pulling power. Just occasionally I'll see it start pulling a few hundred watts.

 

[generaltso]

It will use the AC adapter anytime it needs to charge the 12v (so long as it is actually plugged in) ... not just when it is charging. This is something I learned back in Feb 2021 after I got the car ... there was a software bug. The engineers told me how the software was _supposed_ to work ... and then told me what it actually did (which was the bug). But that bug has long since been fixed.

I have a display inside my house that tells me anytime the car starts pulling power. Just occasionally I'll see it start pulling a few hundred watts.

It will transfer power to the 12V battery when it gets low regardless of whether or not it’s plugged in. But the DC/DC converter only stays engaged when actively charging (or when in Ready mode).

 

[zhackwyatt]

Expecting to replace it every two years here in AZ, just like every other car battery. The heat kills them here, not the cycles.

My C-max battery lasted at least 5 I think. So far MME going on 2.5 years. (fingers crossed.

 

[SpaceEVDriver]

I expect 5-7 years from this battery, on average.
Why? For two main reasons:
1) It's AGM, so it should get double the lifetime of flooded batteries when doing the same duties.
2) It doesn't crank an engine, so the 10C discharge rate seen multiple times a day for ICE batteries doesn't happen. It's not even doing the same duties as many other vehicle LVBs.

 

[shutterbug]

My C-max battery lasted at least 5 I think. So far MME going on 2.5 years. (fingers crossed.

My C-Max batter lasted just about 6 years. So far, I'm on a 3rd MME battery in 2.5 years.

 

[Auto Motive]

Correction to my earlier, I ignored the age-old maxim - RFM - read the frigging manual?‍

How did you attach your charger? Small port or took off shroud?

 

[Teslaeata]

How did you attach your charger? Small port or took off shroud?

Sorry, don’t follow what you’re asking, I may just be being a bit thick.

 

[Reign of Ravens]

How did you attach your charger? Small port or took off shroud?

Sorry, don’t follow what you’re asking, I may just be being a bit thick.

It's a misunderstanding on Auto Motive's part - he's asking how you charged the 12V battery directly (connecting clamps directly to the battery). The document you posted doesn't discuss that, but reinforces what is being said in this thread - that the traction battery (high-voltage battery) charges the 12V battery, and Ford does not expect (or want) us to charge the 12V battery directly, ourselves.

 

[Teslaeata]

It's a misunderstanding on Auto Motive's part - he's asking how you charged the 12V battery directly (connecting clamps directly to the battery). The document you posted doesn't discuss that, but reinforces what is being said in this thread - that the traction battery (high-voltage battery) charges the 12V battery, and Ford does not expect (or want) us to charge the 12V battery directly, ourselves.

Ah, thnx. If my 12v needed charging from external charger it’d have a new one after charge rate of DC to DC converter had been checked.

 

[ChasingCoral]

How did you attach your charger? Small port or took off shroud?

It's a misunderstanding on Auto Motive's part - he's asking how you charged the 12V battery directly (connecting clamps directly to the battery). The document you posted doesn't discuss that, but reinforces what is being said in this thread - that the traction battery (high-voltage battery) charges the 12V battery, and Ford does not expect (or want) us to charge the 12V battery directly, ourselves.

I think @Auto Motive is simply asking about how to connect an external charger to the battery.

Some of us have installed ports in the left beauty cover (shroud) to access the battery directly. There are threads on where to order the ports and how to install them -- even a paper template to use.

If you haven't installed ports, then you have to remove the left beauty cover.

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