Plug in to Maintain 12V Battery??

[E-lectrified]

I have plenty of charge left in the main battery but yet I still get this message every so often. I brought it to the dealer but they said that they couldn't find anything wrong with the car.

Anyone else dealing with this and if so, is there a fix?

I've thought about connecting a trickle charger up to the 12V battery (wherever that is) and let it charge overnight but I don't want to upset the computers.

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[4wheeldog]

How old is the 12v battery? How often and how far do you drive? The low voltage battery charges when the car is being used. And lots of folks report the battery can fail when it is 3 years old.

 

[RickMachE]

Do not sit in Accessory Mode, always have car running.
Do not leave anything plugged in like a dash camera.

If you decide to use a battery maintainer, hook it to posts under driver's side panel, and let it sit at least overnight.

 

[Mach-Lee]

It means the 12V battery is low, so you should think about why that has occurred. As mentioned above, if you run the car in accessory mode or are opening and closing a lot of doors, that can drain the battery. Or you could have some accessory like a dashcam draining it. For more information about drain sources, see this topic: https://www.macheforum.com/site/thr...-system-drain-service-required-message.36140/

 

[E-lectrified]

How old is the 12v battery? How often and how far do you drive? The low voltage battery charges when the car is being used. And lots of folks report the battery can fail when it is 3 years old.

The car is a 2021 model and that's how old the 12V battery is. I guess you're saying that the battery might be coming to the end of its life. Would a replacement be covered under warranty?

 

[E-lectrified]

Do not sit in Accessory Mode, always have car running.
Do not leave anything plugged in like a dash camera.

If you decide to use a battery maintainer, hook it to posts under driver's side panel, and let it sit at least overnight.

All good advice, thanks!

 

[Mach-Lee]

The car is a 2021 model and that's how old the 12V battery is. I guess you're saying that the battery might be coming to the end of its life. Would a replacement be covered under warranty?

Battery might be going bad if it's the original. The 12V battery is covered by the 3 yr/36k warranty only.

 

[E-lectrified]

It means the 12V battery is low, so you should think about why that has occurred. As mentioned above, if you run the car in accessory mode or are opening and closing a lot of doors, that can drain the battery. Or you could have some accessory like a dashcam draining it. For more information about drain sources, see this topic: https://www.macheforum.com/site/thr...-system-drain-service-required-message.36140/

I don't have a dash cam but thanks for the link, I'll check it out.

 

[E-lectrified]

Battery might be going bad if it's the original. The 12V battery is covered by the 3 yr/36k warranty only.

I think that gives be about a month or so to have it replaced under warranty.

 

[MikeC]

I was under the impression that if the 12V battery voltage was dropping then the drive batteries automatically charge it.

 

[Doobster6]

Do not sit in Accessory Mode, always have car running.
Do not leave anything plugged in like a dash camera.

If you decide to use a battery maintainer, hook it to posts under driver's side panel, and let it sit at least overnight.

…..and I assume one would switch everything else off, like radio and climate control system? And you’re saying that unless the car is ‘always running’, the 12v battery will NOT charge as necessary? This has been confusing for me…..I thought it would if it were plugged in, even if it wasn’t ‘running’.

 

[Adventureboy]

I was under the impression that if the 12V battery voltage was dropping then the drive batteries automatically charge it.

The MME first sends the message the OP has posted, then puts the car in Deep Sleep mode shutting off all non-essential modules including the modem that is needed for FordPass, and then charges the 12v battery from the HVB. This is a normal process for vehicles driven for short periods, use of accessory mode, or longer-term non-use. Usually 5-7 days of inactivity on a healthy battery - shorter periods with an aging battery will trigger this process.
If the 12v battery is weak, it may not get through the process above causing dead 12v battery lockouts.
Also, if you are already at your target SOC for the HVB, plugging it in will do nothing for the 12v battery as it only charges this battery when the HVB is actively charging. The process above should still kick in as needed if the 12v battery is healthy.

 

[PsYfY]

I have this issue as well on my 2023 MME Premium. First time it happened about 1 month into owning the car I thought it was a fluke. Then it happened again and I brought it in for service. They kept the car for 2 days and said that it was fixed via an update. Then it happened again. Brought it in again, it took them 19 days to get an update that would allegedly fix it. Then yesterday I received the alert again so it clearly has not been able to be fixed.

This is a major problem as this issue has the potential to leave you stranded outside of your car and we are going into the winter months. Looks like Ford has a bug in their software that they are unable to address. I am in conversation with Ford Motor Company and I am going to request a buyback because I am not convinced they can fix this issue. It is a shame Ford does not have better support for their EVs. Really love the MME and I am happy with owning an EV, just not assured that Ford is a reputable brand.

 

[Maquis]

I have this issue as well on my 2023 MME Premium. First time it happened about 1 month into owning the car I thought it was a fluke. Then it happened again and I brought it in for service. They kept the car for 2 days and said that it was fixed via an update. Then it happened again. Brought it in again, it took them 19 days to get an update that would allegedly fix it. Then yesterday I received the alert again so it clearly has not been able to be fixed.

This is a major problem as this issue has the potential to leave you stranded outside of your car and we are going into the winter months. Looks like Ford has a bug in their software that they are unable to address. I am in conversation with Ford Motor Company and I am going to request a buyback because I am not convinced they can fix this issue. It is a shame Ford does not have better support for their EVs. Really love the MME and I am happy with owning an EV, just not assured that Ford is a reputable brand.

You need to find a dealer with enough competence to diagnose and fix your problem.

 

[E-lectrified]

If you decide to use a battery maintainer, hook it to posts under driver's side panel, and let it sit at least overnight.

Can you be more specific as to this panel's location?

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