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Model 3 12v battery dead
- Thread starter JTesmod3
- Start date
This seems to be the best strategy.
1. Hide a 12v A23 battery behind the tow access cover, so you can open the frunk if your car's 12v is dead.
2. Keep a battery jump starter in the frunk, to allow you to start the car and drive to a service center,
1. Hide a 12v A23 battery behind the tow access cover, so you can open the frunk if your car's 12v is dead.
2. Keep a battery jump starter in the frunk, to allow you to start the car and drive to a service center,
smatthew
Active Member
This seems like too much work for something that will probably never occur.
And if your battery dies suddenly, there is a very big chance that a battery jump starter won't be able to raise the voltage enough to get the car started because at that point the 12V battery will be acting like a giant current sink.
If the car stopped charging the 12V battery, there's a good reason. Charging a battery that failed leads to bad things happening.
AND, EVERYTHING YOU WANT TO ACCOMPLISH CAN BE ACCOMPLISHED WITH A HELPFUL STRANGER WITH JUMPER CABLES.....
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android04
Active Member
The only references are that I've tried it, and it states the exact same thing in the owner's manual. I'm sure if you wanted to you could find YouTube videos showing the same. But by all means, you should try it. Then you will have practice and know what to do if your 12v battery dies.
JetFalcon
Member
If 12V battery means, rotten egg smell, only the small battery not the battery that fuels the car.
I went on the Tesla App or called Tesla, they picked up the car same day and got a battery swapped right away. No money charged, it was still under warranty at the time, car was still about 2 years old, under 3 years old.
I went on the Tesla App or called Tesla, they picked up the car same day and got a battery swapped right away. No money charged, it was still under warranty at the time, car was still about 2 years old, under 3 years old.
It really isnt much work, it's going to take about 5 minutes to hide a battery, and a lot of people already own battery power packs as it is way more convenient than having to ask a stranger. You can buy them at costco for less than $100.
Living in Vegas, the desert heat ruins lead-acid batteries in general and isn't limited to Tesla. It definitely isnt rare for them to suddenly have no power without warning.
If you dont live in the desert heat, you are probably right though, it might be pretty unlikely.
so how did you test the A23? you disconnected the 12V first?
surprising that such small batteries can provide sufficient current to pop open the frunk, with the A23 being less than half the size of a 9V, therefore less than half the current output.... it appears that standard alkaline 9V are about 500maH whereas A23's are 50-100maH. So quite a bit less current output from an A23.
(anybody know the current required to pop the frunk?)
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android04
Active Member
I tested it by unlocking my car and popping open the frunk 3 times. If I ever have issues with the A23 not putting out enough current, I can use 2 in parallel because I put 2 behind the tow hook cover in a ziplock bag. They come 2 to a pack and 2 for perfectly behind the tow hook cover.
Could the leads in the tow hook cover just signal the hood actuator and it’s really getting the power from the cars 12v battery? I think it really needs to be tested with the 12v disconnected, to see if the a23 has enough energy to power the hood actuator, if your 12v was truly dead. Has anyone tested it with a dead/disconnected battery?
As far as a jumper battery. I picked up the Hulkman 85, came shipped with 75% SOC. Tested it on a g35x with a completely dead battery and it started right up. I‘d imagine it would do the job closing the contactors on a Tesla.
Dolemite
is my name
No - it gets power from emergency leads. I've tested it - others on here have, too.
Yeah, I had this question also, as it is surprising to me that a tiny A23 battery (50-100maH) has enough juice to power whatever solenoid pops the frunk open. Already it is surprising that a 9V battery (500maH) has enough, but its somewhat more plausible. Does a zinc-carbon (non-alkaline) 9V have enough juice to work? They are typically rated at 400maH, a bit less than alkaline, though more than the A23. But of course the internal resistance/high current discharge characteristics are different...
Some one should just measure the current (power) needed.
Dolemite
is my name
What happens if you disable HV + 12V battery and close everything?
Does anyone know what happens if you disconnect the 12V battery, disable the high voltage battery, and shut the doors & hood? Does this mean you're SOL? I haven't managed to do this (yet). Not sure how the dead 12V + auxiliary frunk opening "works." I know you can only open the frunk when 12V...
teslamotorsclub.com
android04
Active Member
The reason the A23 or 9V battery put out enough current to work is that the frunk latches are not normal electromagnetic solenoids that directly pull on the release cable. They are actuated by an electric motor that is geared down to pull a steel cable. I'm pretty sure there's a worm gear in there. But my point is that not a lot of torque (and therefore current) is needed because of the mechanical advantage of the gearing. If you pay attention from right by the frunk latch when you pop it open, you will hear motor noise for a fraction of a second before it unlatches.
Good to know. I feel more comfortable with the emergency setup I have. Just need to find a dime bad for the A23 I bought lol. Tape it up behind the tow hook cover and keep the Hulkman jump starter in the frunk.
Apologies if this is in the wrong section but I wanted to see if anyone else has experienced this problem recently. I made a similar post on my local Model 3 group on facebook and someone else had commented they had the exact same problem just yesterday and they were still waiting for a fix from Tesla.
Long story short, my car is completely dead, doors won't unlock, can't wake from app, nothing works. Can't even open frunk with the 12v emergency release. Car just got towed and is going to the service center.
2021 SR+, less than 2 months old with <1500 KM.
Long story short, my car is completely dead, doors won't unlock, can't wake from app, nothing works. Can't even open frunk with the 12v emergency release. Car just got towed and is going to the service center.
2021 SR+, less than 2 months old with <1500 KM.
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