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12v battery/circuit design not reliable for critical functionality

Goldzw

Member
Oct 19, 2019
11
1
Pennsylvania
The 12v battery in my 2014 model S died or the circuit disconnected on me without warning at all. I was locked out of the car completely. Even after the towing company forced open the door the car could not start, completely dead with no warning at all. I had to pay $300 for the towing company to do the force open and get the car to the dealer. I think the design of the 12v circuit is problematic. A critical function of opening the car door and starting a car can not rely only on a single battery or a non-redundant wire! Tesla refused to respond to my comment on the design.
 

Tam

Well-Known Member
Nov 25, 2012
9,465
8,622
Visalia, CA
...single battery or a non-redundant wire! Tesla refused to respond to my comment on the design.

I think that's the best design that all electric cars and not just Tesla are using currently.

There have been attempts in the past to get rid of a separate 12V battery but it was not good.

There are talks for Model Y to get rid of 12V system again but I'll believe it when I see it!
 

Akikiki

A'-Lo-HA ! y'all
Nov 26, 2012
6,511
4,868
Kaneohe, HI
Tesla refused to respond? You mean the statement that the entire company made to you was "we refuse to comment"? I doubt they stopped what they are doing to make a statement. So where it is written that Tesla owes you a response?

Sorry you had trouble getting into your car. But when you say a towing company had to force open the door, it does not sound like they tried jumping the 12V battery behind the nosecone. There's been reports over the last couple of years of the 12V battery failing. And those reports are mostly combined with an admittance that the car has provided warnings that the 12V battery needs to be replaced. Are you certain yours has not been also providing messages and were dismissed.

And a dead battery would not prevent any other car on the road from starting, right? Is every other car on the road equipped with a problematic design? Why not fix yours? Add a second battery to your S if you don't like the way it behaves.
 

brkaus

Well-Known Member
Jul 8, 2014
8,086
6,645
Austin, TX
The 12v battery in my 2014 model S died or the circuit disconnected on me without warning at all. I was locked out of the car completely. Even after the towing company forced open the door the car could not start, completely dead with no warning at all. I had to pay $300 for the towing company to do the force open and get the car to the dealer. I think the design of the 12v circuit is problematic. A critical function of opening the car door and starting a car can not rely only on a single battery or a non-redundant wire! Tesla refused to respond to my comment on the design.

am I missing something? Every ICE car requires a functional 12v battery to start the car (at least all automatics).

yes, they have keys, so doors can be opened. So that does help.

what do you mean by force the doors open? The manual shows how to open the nose cone and attach jumper cables (or preferably a battery booster) to the 12v to restore functionality.
 
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SSedan

Active Member
Jul 24, 2017
2,948
2,589
Greenville Wisconsin
So Tesla is awful because you hired a tow company ignorant of how to handle a Tesla?

My 2014 S and my wife's 2014 Impala needed new 12volts last year.
Usually a Tesla will give you an actual warning where ICE usually do not.
 

Goldzw

Member
Oct 19, 2019
11
1
Pennsylvania
am I missing something? Every ICE car requires a functional 12v battery to start the car (at least all automatics).

yes, they have keys, so doors can be opened. So that does help.

what do you mean by force the doors open? The manual shows how to open the nose cone and attach jumper cables (or preferably a battery booster) to the 12v to restore functionality.
The tesla rep was on the line. She was working with the certified towing company. Guess they should know what you know.
 
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Goldzw

Member
Oct 19, 2019
11
1
Pennsylvania
I think that's the best design that all electric cars and not just Tesla are using currently.

There have been attempts in the past to get rid of a separate 12V battery but it was not good.

There are talks for Model Y to get rid of 12V system again but I'll believe it when I see it!
I do not know about this design. Do you know? The general rules in designing critical functionality is to build-in redundancy. What happened with my model S failed to show such functionality. There was no warning message. The door could not open. The funny thing was the car came back to life right on the towing truck after being shaken up and down on the road, another evidence about some flimsy design with the 12v circuit
 

Goldzw

Member
Oct 19, 2019
11
1
Pennsylvania
So Tesla is awful because you hired a tow company ignorant of how to handle a Tesla?

My 2014 S and my wife's 2014 Impala needed new 12volts last year.
Usually a Tesla will give you an actual warning where ICE usually do not.
It is the towing company called in by tesla reps on the line!
 

Goldzw

Member
Oct 19, 2019
11
1
Pennsylvania
am I missing something? Every ICE car requires a functional 12v battery to start the car (at least all automatics).

yes, they have keys, so doors can be opened. So that does help.

what do you mean by force the doors open? The manual shows how to open the nose cone and attach jumper cables (or preferably a battery booster) to the 12v to restore functionality.
As tesla model s does not use mechanical key, thIs puts additional criticality to 12v battery and its circuit. The obvious lack of redundancy on this battery/circuit and no warning before possible failure is exactly the problem I am talking about here. This is particularly true with a car that does not use a mechanical key.
 

Goldzw

Member
Oct 19, 2019
11
1
Pennsylvania
Tesla refused to respond? You mean the statement that the entire company made to you was "we refuse to comment"? I doubt they stopped what they are doing to make a statement. So where it is written that Tesla owes you a response?

Sorry you had trouble getting into your car. But when you say a towing company had to force open the door, it does not sound like they tried jumping the 12V battery behind the nosecone. There's been reports over the last couple of years of the 12V battery failing. And those reports are mostly combined with an admittance that the car has provided warnings that the 12V battery needs to be replaced. Are you certain yours has not been also providing messages and were dismissed.

And a dead battery would not prevent any other car on the road from starting, right? Is every other car on the road equipped with a problematic design? Why not fix yours? Add a second battery to your S if you don't like the way it behaves.

the towing company was called by the tesla rep and they worked with each other. How did they not know what you knew?
The door does have to be forced open as model S does not use mechanical key. You could not open the trunk as you could with regular car. This puts additional criticality of the 12v battery and circuit far beyond to a regular car. This is exactly the problem I am talking about with the design of a critical functionality.
 

Akikiki

A'-Lo-HA ! y'all
Nov 26, 2012
6,511
4,868
Kaneohe, HI
the towing company was called by the tesla rep and they worked with each other. How did they not know what you knew?
The door does have to be forced open as model S does not use mechanical key. You could not open the trunk as you could with regular car. This puts additional criticality of the 12v battery and circuit far beyond to a regular car. This is exactly the problem I am talking about with the design of a critical functionality.

How would I know why they don't know. But start a survey here and ask how many people know on the 12-15 S that you remove the nosecone to get to battery jumper posts. Once you power the battery, you can open the door. That's why you access the jumper posts.

If you have heartburn with the S's design, sell yours. It is what it is. And Tesla does not owe you an explanation or answer the way I see it. Ask others here.

Again, sorry it cost you $300 to learn what most of us know. I am sure its documented here and Youtube repeatedly.

Even at Tesla not everyone at Tesla knows everything about the different years or models. Yes, to be fully knowledgeable, they should, but that does not change the fact that not all are.
 

Akikiki

A'-Lo-HA ! y'all
Nov 26, 2012
6,511
4,868
Kaneohe, HI
....The general rules in designing critical functionality is to build-in redundancy.
Really? Well get started, you have a billions of existing systems throughout the world to redesign to your specs. :)

What happened with my model S failed to show such functionality. There was no warning message. The door could not open. The funny thing was the car came back to life right on the towing truck after being shaken up and down on the road, another evidence about some flimsy design with the 12v circuit

You just told us what was wrong with your S and explained why there was no message. The door was not suppose to open when there is no 12V current from the battery. There was no message because the 12V battery had not failed. The battery is okay. Maybe its old enough on a '14 to be safe and replace now, but its working.

Yes, funny thing the car came back to life, right after the shaking moved at least one of the cable terminals on the battery or helped the ground strap. It had either a loose battery terminal or the terminal was corroded - LIKE ANY OTHER CAR COULD HAVE HAD. Maybe it will help to get/replace the existing battery. But I bet the SC is going to find either a loose terminal, corroded terminal or ground strap has corroded to the frame and lost ground connection.

You would have saved your self some less than 110% supportive remarks from folks here (including me) if you had added this to your first post.

The tow driver could have checked the battery for the loose or corroded post. Maybe he did. If he did and found neither was the case, then its a ground strap to the body that needs replacing. We've seen it before.

And a connection is critical to make it run, but Tesla and other manufacturers do not build cars with redundant system because they are not preparing them for a drive to the moon.
 

Goldzw

Member
Oct 19, 2019
11
1
Pennsylvania
How would I know why they don't know. But start a survey here and ask how many people know on the 12-15 S that you remove the nosecone to get to battery jumper posts. Once you power the battery, you can open the door. That's why you access the jumper posts.

If you have heartburn with the S's design, sell yours. It is what it is. And Tesla does not owe you an explanation or answer the way I see it. Ask others here.

Again, sorry it cost you $300 to learn what most of us know. I am sure its documented here and Youtube repeatedly.

Even at Tesla not everyone at Tesla knows everything about the different years or models. Yes, to be fully knowledgeable, they should, but that does not change the fact that not all are.
I do not know what you think. I believe manufacturers and distributors have liability for faulty design and faulty product.
 

Goldzw

Member
Oct 19, 2019
11
1
Pennsylvania
Really? Well get started, you have a billions of existing systems throughout the world to redesign to your specs. :)

You just told us what was wrong with your S and explained why there was no message. The door was not suppose to open when there is no 12V current from the battery. There was no message because the 12V battery had not failed. The battery is okay. Maybe its old enough on a '14 to be safe and replace now, but its working.

Yes, funny thing the car came back to life, right after the shaking moved at least one of the cable terminals on the battery or helped the ground strap. It had either a loose battery terminal or the terminal was corroded - LIKE ANY OTHER CAR COULD HAVE HAD. Maybe it will help to get/replace the existing battery. But I bet the SC is going to find either a loose terminal, corroded terminal or ground strap has corroded to the frame and lost ground connection.

You would have saved your self some less than 110% supportive remarks from folks here (including me) if you had added this to your first post.

The tow driver could have checked the battery for the loose or corroded post. Maybe he did. If he did and found neither was the case, then its a ground strap to the body that needs replacing. We've seen it before.

And a connection is critical to make it run, but Tesla and other manufacturers do not build cars with redundant system because they are not preparing them for a drive to the moon.
Really? Well get started, you have a billions of existing systems throughout the world to redesign to your specs. :)



You just told us what was wrong with your S and explained why there was no message. The door was not suppose to open when there is no 12V current from the battery. There was no message because the 12V battery had not failed. The battery is okay. Maybe its old enough on a '14 to be safe and replace now, but its working.

Yes, funny thing the car came back to life, right after the shaking moved at least one of the cable terminals on the battery or helped the ground strap. It had either a loose battery terminal or the terminal was corroded - LIKE ANY OTHER CAR COULD HAVE HAD. Maybe it will help to get/replace the existing battery. But I bet the SC is going to find either a loose terminal, corroded terminal or ground strap has corroded to the frame and lost ground connection.

You would have saved your self some less than 110% supportive remarks from folks here (including me) if you had added this to your first post.

The tow driver could have checked the battery for the loose or corroded post. Maybe he did. If he did and found neither was the case, then its a ground strap to the body that needs replacing. We've seen it before.

And a connection is critical to make it run, but Tesla and other manufacturers do not build cars with redundant system because they are not preparing them for a drive to the moon.



Such reliability would be required for critical functionalities or the design would be considered faulty. The manufacturers and distributors would be held liable.
 

Goldzw

Member
Oct 19, 2019
11
1
Pennsylvania
Really? Well get started, you have a billions of existing systems throughout the world to redesign to your specs. :)



You just told us what was wrong with your S and explained why there was no message. The door was not suppose to open when there is no 12V current from the battery. There was no message because the 12V battery had not failed. The battery is okay. Maybe its old enough on a '14 to be safe and replace now, but its working.

Yes, funny thing the car came back to life, right after the shaking moved at least one of the cable terminals on the battery or helped the ground strap. It had either a loose battery terminal or the terminal was corroded - LIKE ANY OTHER CAR COULD HAVE HAD. Maybe it will help to get/replace the existing battery. But I bet the SC is going to find either a loose terminal, corroded terminal or ground strap has corroded to the frame and lost ground connection.

You would have saved your self some less than 110% supportive remarks from folks here (including me) if you had added this to your first post.

The tow driver could have checked the battery for the loose or corroded post. Maybe he did. If he did and found neither was the case, then its a ground strap to the body that needs replacing. We've seen it before.

And a connection is critical to make it run, but Tesla and other manufacturers do not build cars with redundant system because they are not preparing them for a drive to the moon.
Really? Well get started, you have a billions of existing systems throughout the world to redesign to your specs. :)



You just told us what was wrong with your S and explained why there was no message. The door was not suppose to open when there is no 12V current from the battery. There was no message because the 12V battery had not failed. The battery is okay. Maybe its old enough on a '14 to be safe and replace now, but its working.

Yes, funny thing the car came back to life, right after the shaking moved at least one of the cable terminals on the battery or helped the ground strap. It had either a loose battery terminal or the terminal was corroded - LIKE ANY OTHER CAR COULD HAVE HAD. Maybe it will help to get/replace the existing battery. But I bet the SC is going to find either a loose terminal, corroded terminal or ground strap has corroded to the frame and lost ground connection.

You would have saved your self some less than 110% supportive remarks from folks here (including me) if you had added this to your first post.

The tow driver could have checked the battery for the loose or corroded post. Maybe he did. If he did and found neither was the case, then its a ground strap to the body that needs replacing. We've seen it before.

And a connection is critical to make it run, but Tesla and other manufacturers do not build cars with redundant system because they are not preparing them for a drive to the moon.

maybe you don’t care but yes they will have to eventually build such critical reliabilities in their cars. As for driving to the moon let us dream about it and there will be another spec.
 

Tam

Well-Known Member
Nov 25, 2012
9,465
8,622
Visalia, CA
...A critical function of opening the car door and starting a car can not rely only on a single battery or a non-redundant wire! Tesla refused to respond to my comment on the design.

As others have explained above, there is redundancy when your 12V battery fails:

1) As instructed by owner's manual, battery jump to supply your car with 12V so its accessories including doors would work again.

2) Your front doors are mechanical and not just electronic so you can mechanically slip a rod through your car's window to hook on the interior door handle and open your door.

aid1985973-v4-728px-Use-a-Coat-Hanger-to-Break-Into-a-Car-Step-9-Version-3.jpg.webp
 

swegman

Active Member
Mar 27, 2012
1,580
1,641
the towing company was called by the tesla rep and they worked with each other. How did they not know what you knew?
The door does have to be forced open as model S does not use mechanical key. You could not open the trunk as you could with regular car. This puts additional criticality of the 12v battery and circuit far beyond to a regular car. This is exactly the problem I am talking about with the design of a critical functionality.

I’m sorry you had problems but it’s not any more of an issue than on any other car.

I have a 2013 P85. I’ve had 2 replacement batteries installed; the first within the first year of ownership and the second battery replaced about 9 months ago. In both cases the car provided notice on the instrument cluster (not the touchscreen) that the 12 volt battery required service. It’s not a large type font notice so perhaps you overlooked it.

In any event, when the 12 volt battery dies, the doors will not unlock. You simply pop off the nosecone and there are two terminals that a charger, jumper cables or alternative 12 volt source (battery) can be attached to. At that point your doors will be operational and you should be able to “start” the car.

It is no more difficult than if the 12 volt battery dies on an ICE car. And the procedure to jump start the car is the same on both types of cars.

You did really good if you got 4 plus years of life from the battery. It usually doesn’t last that long due to the constant discharge it is subjected to. A replacement battery costs about $200 I believe. What solution do you propose? Adding a second 12 volt battery? The second battery could die at the same time as the first battery, and would add needless weight and cost to the car. There are many things that could be better designed on the car (such as a larger, more powerful battery), but the 12 volt battery system (circuit) is not one of them.

BTW, if you have owned the car so long, why have you only joined TMC today, and to complain about the 12 volt battery dying? Also, what good is it that you can unlock an ICE car with a key if you still are unable to start the car because it has a dead battery?
 
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