12v battery must be replaced soon

[talononeguy]

I purchased my RWD LR TM3 in August 2018. I have only 11,900 miles on it.
I have had no warnings yet, but stopped by my SC and asked if they could check my battery. Remotely, the SC told me my battery was showing 14.5 volts. He thought I should be good for quite a while. However, some people are experiencing sudden battery failure with no warning. When this happens, are these batteries that have a sudden catastrophic cell failure, rather than gradual degradation? If so, my service center's reassurance gives me little comfort.

My technician said that my voltage was on the low side leading to the warning message. He said it might have lasted until my appointment 3 weeks in the future. I don't think most are having a full catastrophic cell failure which would render the battery completely dead. If that was the case, most would never even get the '12v battery must be replaced soon.'

I'm not sweating it, and I wouldn't if I were you either. I just simply sweat the summer in Florida!

 

[iwannam3]

RTFM first.

https://34c9c8a1-7edd-4e5b-8d85-78f...a10dd8bd324d1bb3b0537bf065ea86.pdf?index=true

Those instructions are not for a simple battery swap. They are for Disconnecting 12V and High Voltage Power to reset DC/DC

 

[iwannam3]

I have the one Costco has been selling for sometime. I won't say it's the best, it was a good price with a discount at the time, at around $39.99. In fact, it's on sale again.

https://www.costco.com/type-s-lithi...nk-with-led-flashlight.product.100425276.html

So for this to work, you need to have a 9 v battery where? I don't carry one around. Is there a plastic flap under the body or bumper one could be stashed at, like a spare key?

 

[israndy]

You can use the new battery or the jumpstart battery to unlock it. The 9v is simply a small battery that can do it too.

I am driving a March 2018 LR RWD with about 60,000 miles and I am on the original battery, but my warranty ended at 50K miles so if it does go out I'm gonna have to get one of those lithium batts.

 

[vickh]

EV Nation..............It doesn't do any good to carry a 12V pack in the car. When it dies you can't get in....and it can die without any warning,,,,,,,I know. Never count on a warning. The best indication is that the battery is about 2 years old....then be aware.

one year in AZ. Mine was replaced while at SC, they said they smelt something (and it wasn't the AC!)

 

[vickh]

You can use the new battery or the jumpstart battery to unlock it. The 9v is simply a small battery that can do it too.

I am driving a March 2018 LR RWD with about 60,000 miles and I am on the original battery, but my warranty ended at 50K miles so if it does go out I'm gonna have to get one of those lithium batts.

where do you connect the 9V to jump??

 

[SageBrush]

Those instructions are not for a simple battery swap. They are for Disconnecting 12V and High Voltage Power to reset DC/DC

https://www.ohmmu.com/tesla3

 

[RayK]

where do you connect the 9V to jump??

The "9V" battery people are referring to here is only to get the frunk open and not to "jump" the car's 12V battery. There are two wires hidden behind the tow hook cover on the front bumper. Application of a voltage across those wires is supposed to trigger the electric latch holding the hood down. This is the only way to get into the frunk when the car's 12V battery is dead. You can then take off the plastic cover hiding the 12V battery and jump it to start the car.

And by that I mean to use the normal method of using another car or portable jumpstarter battery. Not the 9V.

 

[danarcha]

For me, I got in the car at work to head home, the warning was on the screen to replace the 12v battery soon and there were a bunch of errors as well, on the way home I stopped to pick up my little one and when she went to get in the car, her window rolled down and wouldnt go back up and the car wouldnt move and the screen wouldnt turn on at all. After a minute or less all four windows rolled down super slow and I was dead in the water.

What's the deal with the windows rolling down when the battery fails? Does that always happen? So if my battery goes dead during a rainstorm I have to worry about the inside getting soaked too? This sounds like a bad design.

 

[Avid]

So for this to work, you need to have a 9 v battery where? I don't carry one around. Is there a plastic flap under the body or bumper one could be stashed at, like a spare key?

As other have said, the 9v will get the frunk to open, you have the jump battery in the frunk and use it after you get the frunk open.

 

[israndy]

What's the deal with the windows rolling down when the battery fails? Does that always happen? So if my battery goes dead during a rainstorm I have to worry about the inside getting soaked too? This sounds like a bad design.

I assume that's to cover you if you drive into a lake. If the battery fails and the windows can't be rolled down and water pressure holds the door closed you may die in the car.

 

[SageBrush]

What's the deal with the windows rolling down when the battery fails?

At least in part, to protect the glass from breaking when you open doors.

 

[toolman335]

What a brutal design. There's no way to manually open the frunk? So if we're on a trip we'd have to have a 9V battery to open the frunk and then jumpstart the 12V?

 

[toolman335]

The "9V" battery people are referring to here is only to get the frunk open and not to "jump" the car's 12V battery. There are two wires hidden behind the tow hook cover on the front bumper. Application of a voltage across those wires is supposed to trigger the electric latch holding the hood down. This is the only way to get into the frunk when the car's 12V battery is dead. You can then take off the plastic cover hiding the 12V battery and jump it to start the car.

And by that I mean to use the normal method of using another car or portable jumpstarter battery. Not the 9V.

We all understand that connecting a 9V to those wires is how the frunk is popped open. The question is HOW to connect the wires to the 9V. Can anyone explain that process? The tiny 9V battery is going to get us out of a major jam someday. I'd love to know exactly how to use it.

 

[Sophias_dad]

We all understand that connecting a 9V to those wires is how the frunk is popped open. The question is HOW to connect the wires to the 9V. Can anyone explain that process? The tiny 9V battery is going to get us out of a major jam someday. I'd love to know exactly how to use it.

Instead of a jump starter, a 9v battery will work. Connect the red lead from the car to the smaller of the two connections on the 9V.

Be aware that popping that little circular cover off comes with a pretty high chance of damaging the cover.

 

[smatthew]

When you break the tow port cover, just put in a mobile service request. Once you confirm to the mobile tech that you attempted to open it the correct way (pushing in at 1 o'clock), they'll replace it for free. DO NOT BUY ONE ON EBAY! If you don't want to deal with a service visit Tesla will sell you a Tow Port cover for under $10. People on eBay are charging $55 or more!

 

[toolman335]

Instead of a jump starter, a 9v battery will work. Connect the red lead from the car to the smaller of the two connections on the 9V.

Be aware that popping that little circular cover off comes with a pretty high chance of damaging the cover.

When you say connect, do you mean simply tap both connections to the battery? How would you "connect?"
If you already have a jump starter, why would you want a 9v battery? Is it safer/gentler? The video is pretty simple with a jump starter. Thanks for sharing!

 

[smatthew]

a 9v battery is the smallest power source that will open the frunk. If you have a 12V source, like a jump starter, that will work fine.

You just hold the wires to the battery until the frunk opens.

Using a jump starter is neither safer or gentler. It works exactly the same.

But most people aren't going to keep a jump starter in their pocket. You could probably convince your wife to throw a 9v battery in her purse if she carries one. And more stores sell 9v batteries than 12v batteries.

Of course, the car rolls down the windows when the battery dies. Why doesn't it also pop the frunk?

 

[SageBrush]

why would you want a 9v battery?

Two reasons

1. My jump battery is in my frunk ... which might be closed
2. A small 9v easily fits in a purse or pouch

 

[RayK]

And if for some reason you do decide to keep a 9V battery in your purse or pocket, please make sure that the two terminals are covered with some tape or the battery is inside a non-conductive enclosure. That way it will not accidentally be shorted out by loose change in the same purse or pocket. It should not cause any fire or personal damage if it does short out (9V has a very low current capacity) but if you think you're going to be rescued by that battery, give it the best chance of survival. Along those lines, I would recommend that you use a good alkaline battery and not a rechargeable one (e.g., NiMH) as those self-discharge at a much higher rate.