12-volt went blank

[Sir Barton]

I am hoping some of you more technically-savvy folks out there can help me with this one. We took the
ME to run a few errands Saturday, certainly not more than 40 miles. We did not try to use it again until mid afternoon Monday. But when I hopped into the driver's seat, I noticed everything was blank inside: no lights, not bells, no whistles. Dead. I then noticed a message I had overlooked from Sunday on my Ford phone app: "Please plug in Sir Barton to recharge its battery. Its voltage is low, which would make it difficult to start your vehicle." I am pretty sure it was plugged in, as do instinctively every time we pull into the garage. With help from a phone call to our local Ford dealer, I was directed to the actual 12-volt battery and instructed how to get at it; it is a difficult angle to get the cables on, but with much help I managed. Sir Barton, as we named our ME for the Ford app, came back to life; I left the cables on to charge it up for about 45 minutes, and it ran fine (well, sort of. more on that in a minute.)
So, what in the heck caused it, and why? The only thing I can figure is maybe I left the vehicle on when we exited the car Saturday. I was distracted by two dogs begging to get out of the car and the engine makes no noise, so it was bound to happen sooner or later. Or maybe a knee hit the headlights knob and turned them permanently on instead of on auto? Or something else?
Another thing: when I first called the local dealer, the service guy was able to access Sir Barton's immediate vitals tell me the car's 12-volt was down to just 28 percent. I have tried but cannot find this feature for the 12 volt charge. Any ideas where it is?
I didn't dare turn the car off and on again before test driving it around the neighborhood first. But, on this test drive, the car accelerated fairly aggressively in reverse and forward without me touching the pedal. I had to brake often, just the opposite of its normal state. When I got back, I turned it off and on. Everything worked fine after that. Following the test drive, there was another notice on my Ford phone app: Power train Malfunction/Reduced Power.
Since then I have received no new notices and Sir Barton is working fine as always. I am going to schedule her today for a slightly overdue checkup at the Ford place.
Sorry for the long message, but any insight would be helpful.
Thanks - Larry

Sponsored

 

[dtbaker61]

from your signature, it looks like you have a 2021.
you *most likely* need to replace the 12v battery. They have a 36mo warranty, and with reduced capacity over time they can fail 'suddenly and without warning' in an EV.

you got one warning, that's about all you are going to get, and it could fail at any time... order a replacement from RockAuto, or your dealership, ASAP

It's not like a regular starter battery when you can sometimes hear it getting tired.

 

[Sir Barton]

Thanks much. And, yes, I neglected to mention it is a 2021. I will add new battery to the list during the checkup.

 

[electric-in-the-desert]

Yeah certainly sounds like a dying 12 volt. That can cause the car to do all sorts of weird things, including throw random error codes. There has been an influx of these posts the last week or so… You can check the 12v at this link https://www.ford.com/myaccount/account-dashboard (under charge level, that is LVB, not the HVB) OR with an OBD adapter + an app like car scanner

 

[Sir Barton]

Yeah certainly sounds like a dying 12 volt. That can cause the car to do all sorts of weird things, including throw random error codes. There has been an influx of these posts the last week or so… You can check the 12v at this link https://www.ford.com/myaccount/account-dashboard (under charge level, that is LVB, not the HVB) OR with an OBD adapter + an app like car scanner

?

 

[JoanS]

Why are these batteries failing at around 3 years. Shouldn't they last longer then that?

 

[shutterbug]

Why are these batteries failing at around 3 years. Shouldn't they last longer then that?

Can't tell why, but before my '21 was totaled, I was on LVB #4. All replaced under warranty.

 

[electric-in-the-desert]

Why are these batteries failing at around 3 years. Shouldn't they last longer then that?

Seems like a mix of the LVB has a decent amount of responsibility in the machE architecture (particularly for OTAs and PAAK) + they’ve had trouble nailing down the software to manage the LVB.

 

[JohnFoxeSheets]

With help from a phone call to our local Ford dealer, I was directed to the actual 12-volt battery and instructed how to get at it; it is a difficult angle to get the cables on, but with much help I managed. .... I left the cables on to charge it up for about 45 minutes, and it ran fine (well, sort of. more on that in a minute.)

Did you connect the charging cables directly to the battery? There are two spots to attach charging cables to that are readily accessible once the trim panel to the right of the frunk is removed. It is very important to use these two spots for charging as otherwise the battery management system (BMS) will not "know" that the 12V battery was charged. Also, 45 minutes charging a dead battery is not much. It would be best to leave it on the charger for at least over night. While the car will (try to) maintain the battery, it sometimes needs a bit of help - especially with an old, dying battery, which sadly yours appears to be.

I have tried but cannot find this feature for the 12 volt charge. Any ideas where it is?

Ford automatically gets that data reported to it by the car, and the dealership can access it to. So can you, though it's a bit obscure. You can see it here. The Charge Level reported is the 12V battery, not your HVB. Note that this value is the last value reported to Ford, and so it can be out of date. If you want to get the current value, you can wake the car up (e.g., lock or unlock it). That will send a new value to Ford but it will also use up some (12V) battery power, thereby lowering the state of charge.

I didn't dare turn the car off and on again before test driving it around the neighborhood first. But, on this test drive, the car accelerated fairly aggressively in reverse and forward without me touching the pedal. I had to brake often, just the opposite of its normal state. When I got back, I turned it off and on. Everything worked fine after that. Following the test drive, there was another notice on my Ford phone app: Power train Malfunction/Reduced Power.
Since then I have received no new notices and Sir Barton is working fine as always. I am going to schedule her today for a slightly overdue checkup at the Ford place.
Sorry for the long message, but any insight would be helpful.
Thanks - Larry

My guess is that the 12V battery was still a bit low and that's why you experienced some of the oddness you mention above (not all modules were functioning 100% properly). If it's sorted itself out, then it likely means the 12V is charged to an acceptable level now. But sadly that doesn't mean that your 12V battery is ok. A dying battery can (often) still be charged... It just won't hold the charge as long as it should.

 

[Sikkun]

'suddenly and without warning' in an EV.

Same way my 12v has died on every ICE I have ever had….can’t start the car, jump car, store says battery test “good”, drive home, can’t start car.

No clue what “good” means on a battery tester, but can’t start car = new battery for me.

 

[Sir Barton]

Did you connect the charging cables directly to the battery? There are two spots to attach charging cables to that are readily accessible once the trim panel to the right of the frunk is removed. It is very important to use these two spots for charging as otherwise the battery management system (BMS) will not "know" that the 12V battery was charged. Also, 45 minutes charging a dead battery is not much. It would be best to leave it on the charger for at least over night. While the car will (try to) maintain the battery, it sometimes needs a bit of help - especially with an old, dying battery, which sadly yours appears to be.


Ford automatically gets that data reported to it by the car, and the dealership can access it to. So can you, though it's a bit obscure. You can see it here. The Charge Level reported is the 12V battery, not your HVB. Note that this value is the last value reported to Ford, and so it can be out of date. If you want to get the current value, you can wake the car up (e.g., lock or unlock it). That will send a new value to Ford but it will also use up some (12V) battery power, thereby lowering the state of charge.

My guess is that the 12V battery was still a bit low and that's why you experienced some of the oddness you mention above (not all modules were functioning 100% properly). If it's sorted itself out, then it likely means the 12V is charged to an acceptable level now. But sadly that doesn't mean that your 12V battery is ok. A dying battery can (often) still be charged... It just won't hold the charge as long as it should.

Thanks for the detailed reply. I have already resigned myself to a new battery when I take in for a checkup.

 

[HuntingPudel]

Just a side note that they should not have directed you to charge the 12V battery using the battery posts. Doing so bypasses the BMS sensor. They should have directed you to the jump points under the left side beauty panel. The positive point is covered by a red plastic protector. The negative point is on the left side strut tower. Additionally, they are much easier to access than the posts on the battery. ??

 

[Sir Barton]

Just a side note that they should not have directed you to charge the 12V battery using the battery posts. Doing so bypasses the BMS sensor. They should have directed you to the jump points under the left side beauty panel. The positive point is covered by a red plastic protector. The negative point is on the left side strut tower. Additionally, they are much easier to access than the posts on the battery. ??

Good to know. Thanks

 

[the golden eel]

I am hoping some of you more technically-savvy folks out there can help me with this one. We took the
ME to run a few errands Saturday, certainly not more than 40 miles. We did not try to use it again until mid afternoon Monday. But when I hopped into the driver's seat, I noticed everything was blank inside: no lights, not bells, no whistles. Dead. I then noticed a message I had overlooked from Sunday on my Ford phone app: "Please plug in Sir Barton to recharge its battery. Its voltage is low, which would make it difficult to start your vehicle." I am pretty sure it was plugged in, as do instinctively every time we pull into the garage. With help from a phone call to our local Ford dealer, I was directed to the actual 12-volt battery and instructed how to get at it; it is a difficult angle to get the cables on, but with much help I managed. Sir Barton, as we named our ME for the Ford app, came back to life; I left the cables on to charge it up for about 45 minutes, and it ran fine (well, sort of. more on that in a minute.)
So, what in the heck caused it, and why? The only thing I can figure is maybe I left the vehicle on when we exited the car Saturday. I was distracted by two dogs begging to get out of the car and the engine makes no noise, so it was bound to happen sooner or later. Or maybe a knee hit the headlights knob and turned them permanently on instead of on auto? Or something else?
Another thing: when I first called the local dealer, the service guy was able to access Sir Barton's immediate vitals tell me the car's 12-volt was down to just 28 percent. I have tried but cannot find this feature for the 12 volt charge. Any ideas where it is?
I didn't dare turn the car off and on again before test driving it around the neighborhood first. But, on this test drive, the car accelerated fairly aggressively in reverse and forward without me touching the pedal. I had to brake often, just the opposite of its normal state. When I got back, I turned it off and on. Everything worked fine after that. Following the test drive, there was another notice on my Ford phone app: Power train Malfunction/Reduced Power.
Since then I have received no new notices and Sir Barton is working fine as always. I am going to schedule her today for a slightly overdue checkup at the Ford place.
Sorry for the long message, but any insight would be helpful.
Thanks - Larry

Sorry to hear about your troubles, but on a side note I just wanted to let you know I enjoyed reading your post just based on how it is written. Then after I read it, I notice in your profile you are a writer. Makes sense.

 

[Sir Barton]

Good to know. Thanks

Well, thanks. I do try to make things clear and readable.

Sponsored