12v battery problem can have serious consequences

DevSecOps

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Rock or other implement was my first thought. As a parent, if I was in that situation, that window would have lasted 5 minutes, tops!
Yeah, I just looked up the replacement price of the driver side window through Safelite and it's $335. I would've probably just waited for a tow if the child was safe and warm but if not, why would anyone would even worry about the $335?
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gordonf238

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I feel for her. I personally find the whole idea beyond stupid. First of all, why does an electric vehicle with a 88kw battery rely on a separate battery for rudimentary functions like opening doors? I’m a pilot, and in aviation the key is redundancy, redundancy, redundancy. I obviously don’t expect aviation- level engineering (or logic) in consumer vehicles, but this is a real dumb decision on Ford’s part.

There should have been a mechanical override hidden somewhere underneath the rear bumper that can open a door provided the vehicle is unlocked.

Alternatively, the front cover plate could have housed a mechanical lock where the key (in the key fob) would go to mechanically unlock the doors.

whether you’re a fan boy or not, you have to agree that a state of the art electric vehicle that relies on a century old technology (lead acid battery) to open its doors is a stupid design decision. A decision that’s made more complicated by the fact that the only way to access the lead-acid battery is through an electrically-actuated trunk which requires a secondary 12v power supply.

Stupid, stupid, stupid.
 

SnBGC

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I feel for her. I personally find the whole idea beyond stupid. First of all, why does an electric vehicle with a 88kw battery rely on a separate battery for rudimentary functions like opening doors? I’m a pilot, and in aviation the key is redundancy, redundancy, redundancy. I obviously don’t expect aviation- level engineering (or logic) in consumer vehicles, but this is a real dumb decision on Ford’s part.

There should have been a mechanical override hidden somewhere underneath the rear bumper that can open a door provided the vehicle is unlocked.

Alternatively, the front cover plate could have housed a mechanical lock where the key (in the key fob) would go to mechanically unlock the doors.

whether you’re a fan boy or not, you have to agree that a state of the art electric vehicle that relies on a century old technology (lead acid battery) to open its doors is a stupid design decision. A decision that’s made more complicated by the fact that the only way to access the lead-acid battery is through an electrically-actuated trunk which requires a secondary 12v power supply.

Stupid, stupid, stupid.
Agree in general.
Worst part is they give us a key.......just no lock. ????

Many of us pointed out this lazy design flaw way back in the beginning and we were told the 12v would never go flat.

Wrong. So very very wrong.
What is next? No valve stems on the tires?
 

gordonf238

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Agree in general.
Worst part is they give us a key.......just no lock. ????

Many of us pointed out this lazy design flaw way back in the beginning and we were told the 12v would never go flat.

Wrong. So very very wrong.
What is next? No valve stems on the tires?
I blame the young hot shot in Ford’s marketing team pushing for these types of features to compete with (don’t hold your breath… Tesla). All while forgetting a simple fact - that a car needs to be functional before it’s fashionable.

Imagine pulling over to a rest stop in the middle of a cold, wintry night in a cell-phone dead zone, only to return to your mach-e that won’t unlock.

Hope you have a 12v jump starter in your pocket!
 


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All temperature sensors in the MME read Celsius natively, they are converted to Fahrenheit only for a select group of people. Still laughing?
I am sad that the U.S. is still the only nation using the obsolete Imperial System from the old U.K. and many citizens will not learn the Internstionsl Metric System. As an EE I learned the Metric System in 1970 and use it more than the Imperial System. It is extremely easy to learn as there are just three units: meter, liter, and gram. And Celsius is related to water, so O C is ice and 100 C is steam.

If you need to ask, I am a New Yorker, and more American than anyone else here. That is why I am sad.
 

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I read somewhere that the later production models and/or software updates have some fixes to protect the 12v battery . . . as far as I know that's just a rumor, but I'd love if someone could confirm it? :)
 

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I read somewhere that the later production models and/or software updates have some fixes to protect the 12v battery . . . as far as I know that's just a rumor, but I'd love if someone could confirm it? :)
The earlier production Mach-E's have sensors, hardware, and software in place with the goal of maintaining the 12V battery. I'm not sure what sort of rumor you're hearing (or spreading?) but I'm going to assume later production models are still produced with the intent of maintaining the batteries.
 

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I feel for her. I personally find the whole idea beyond stupid. First of all, why does an electric vehicle with a 88kw battery rely on a separate battery for rudimentary functions like opening doors? I’m a pilot, and in aviation the key is redundancy, redundancy, redundancy. I obviously don’t expect aviation- level engineering (or logic) in consumer vehicles, but this is a real dumb decision on Ford’s part.

There should have been a mechanical override hidden somewhere underneath the rear bumper that can open a door provided the vehicle is unlocked.

Alternatively, the front cover plate could have housed a mechanical lock where the key (in the key fob) would go to mechanically unlock the doors.

whether you’re a fan boy or not, you have to agree that a state of the art electric vehicle that relies on a century old technology (lead acid battery) to open its doors is a stupid design decision. A decision that’s made more complicated by the fact that the only way to access the lead-acid battery is through an electrically-actuated trunk which requires a secondary 12v power supply.

Stupid, stupid, stupid.
Fun fact, a lot of those keyholes are just two micro switches and wouldn’t work with a dead battery either. I’ve seen an F150 completely prevent the fob and keyhole from unlocking any door because of a failure in the rear passenger door latch.
if you think about it, the Mach e is ahead of those vehicles because you CAN access the battery.
either way, all you really need to get in to any vehicle is a door wedge.
 

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The earlier production Mach-E's have sensors, hardware, and software in place with the goal of maintaining the 12V battery. I'm not sure what sort of rumor you're hearing (or spreading?) but I'm going to assume later production models are still produced with the intent of maintaining the batteries.
I would hope so. An ice car with a low battery will be charged by driving it. The opposite of e-cars. Occasional charging just doesn’t get it. It’s common sense, and it appears whatever Ford did isnt enough.
 

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I feel for her. I personally find the whole idea beyond stupid. First of all, why does an electric vehicle with a 88kw battery rely on a separate battery for rudimentary functions like opening doors? I’m a pilot, and in aviation the key is redundancy, redundancy, redundancy. I obviously don’t expect aviation- level engineering (or logic) in consumer vehicles, but this is a real dumb decision on Ford’s part.

There should have been a mechanical override hidden somewhere underneath the rear bumper that can open a door provided the vehicle is unlocked.

Alternatively, the front cover plate could have housed a mechanical lock where the key (in the key fob) would go to mechanically unlock the doors.

whether you’re a fan boy or not, you have to agree that a state of the art electric vehicle that relies on a century old technology (lead acid battery) to open its doors is a stupid design decision. A decision that’s made more complicated by the fact that the only way to access the lead-acid battery is through an electrically-actuated trunk which requires a secondary 12v power supply.

Stupid, stupid, stupid.
I don't know if any manufacturer was able to get rid of 12V battery. I remember Musk was promising to use a supercapacitor instead, but apparently that was just one of his empty promises. Practically all electronics is running of the 12V battery, it cannot run directly of the HVB. But unless there is a defect of some sort, the 12V should be kept charged by the invertor from the HVB, so it should never happen.
Everybody should also get familiar with the procedure how to open the hood and get connected to the 12V terminals when the battery goes bad.
 

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Yeah, I just looked up the replacement price of the driver side window through Safelite and it's $335. I would've probably just waited for a tow if the child was safe and warm but if not, why would anyone would even worry about the $335?
I really love my Mach N Cheese, but child > car and I'd be breaking the window right away. You probably can't mess around with a baby in that kind of cold.
 

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There are more and more cases of failing 12v batteries in parked cars, especially now as winter has arrived.

What we know so far is that the 12V battery in MME is charged to circa 90% 12VSOC (different from the HV battery SOC) and usually remains at 90-85% over night, but sometimes may quickly drop to 70-60% 12VSOC by next morning. Whether it is due to very low temperatures, parasitic power drain from car electronics when car is unplugged/plugged but not charging, or disfunctional components in some cars, is yet to be seen. Parasitic drain (quiescent current) may vary from 15 mA up to 55 mA or more.

These hidden parameters (12V % SOC, quiescent) are not shown on dashboard, but are readable with obd2 dongle and Car Scanner Elm Obd2 app:

https://www.macheforum.com/site/threads/obd2-scanners.13446/#post-329067

https://www.macheforum.com/site/threads/mach-e-dead-again.12086/page-3#post-310520
 

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I feel for her. I personally find the whole idea beyond stupid. First of all, why does an electric vehicle with a 88kw battery rely on a separate battery for rudimentary functions like opening doors?
When I first learned about the 12V battery this is how I felt as well. But drawing power from the 88 kWh HVB is not as easy as drawing power from the LVB. There is an complex battery management system that must heat/cool, monitor and report the status of the HVB when it is used. I think Ford engineers determined the overhead would make using the HVB for low power tasks very inefficient and drain the HVB unnecessarily.

That said, they should have included a jump start button like other car companies have done. Tapping the HVB in an emergency is worth the inefficiency when the LVB is dead
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