Model 3 12v Battery issues, monitoring, Aftermarket replacement

[AlanSubie4Life]

A couple of weeks ago, I set up an appointment with Tesla mobile service to proactively replace the factory lead acid 12 volt battery in my Model 3 with a lithium ion 12 volt battery. It was partly a question to find out if they could do that now. Service said it's not available, so I cancelled the appointment. However, now I see that that refreshed Model S comes with a lithium ion 12 volt battery, which is terrific!

Soooo.... Does anyone know if Tesla is at least planning to offer lithium ion 12 volt battery replacements instead of lead acid batteries?

I doubt it. It's a completely different application with (probably) a totally redesigned subsystem of DCDC converter, etc. The Model 3 would destroy this battery, probably, since it is only 99Wh. (Anyone know the capacity of the Ohmmu for Model 3 (website still doesn't specify it clearly)? Their largest Ohmmu is $1000 but 2kWh of capacity (!!! - much larger than the 500-600Wh of the Model 3 OEM battery).)

I'd just get that Tesla replacement battery on order. I think pandemic exit issues are making lead-acid battery supply chains messed up. But you can have batteries for a good long time at $85 a battery.

 

[samp987]

So M3 Performance is 3yrs old now, tesla mobile proactively replaced my 12V for free on Wednesday (2 days ago) - I wake up this morning to leave, I cannot unplug the charging port, I walk around whole car to unlock the door, nothing. On the APP it connects to car and say I have unlocked the doors, nada, I click open frunk and trunk, app shows I've opened, but in reality nothing on the car opens, it sits there just off/dead. Somehow the only APP control that worked is the Vent Windows button, which only vented the passenger side of car - I got a long stick and clicked the inside door open button on passenger door, and it opened. On the screen I get the 12V error message, still cannot unlock doors or trunk or frunk - I use the emergency frunk open jump start on the fender, and give the 12v a jump for 30 mins, no effect. Inside the car, all drivers side open door buttons/mirror/window does not work along with the entire steering column, horn, hazards, shift/turn stalks do not work. Only thing that turns on is screen. did the power off reset with roadside on the phone, no luck. Cannot drive car or put in tow mode... - Car battery is full 90% capacity - cannot release charging port not even from screen -

https://imgur.com/mM7wSA6

 

[KenC]

So M3 Performance is 3yrs old now, tesla mobile proactively replaced my 12V for free on Wednesday (2 days ago) - I wake up this morning to leave, I cannot unplug the charging port, I walk around whole car to unlock the door, nothing. On the APP it connects to car and say I have unlocked the doors, nada, I click open frunk and trunk, app shows I've opened, but in reality nothing on the car opens, it sits there just off/dead. Somehow the only APP control that worked is the Vent Windows button, which only vented the passenger side of car - I got a long stick and clicked the inside door open button on passenger door, and it opened. On the screen I get the 12V error message, still cannot unlock doors or trunk or frunk - I use the emergency frunk open jump start on the fender, and give the 12v a jump for 30 mins, no effect. Inside the car, all drivers side open door buttons/mirror/window does not work along with the entire steering column, horn, hazards, shift/turn stalks do not work. Only thing that turns on is screen. did the power off reset with roadside on the phone, no luck. Cannot drive car or put in tow mode... - Car battery is full 90% capacity - cannot release charging port not even from screen -

https://imgur.com/mM7wSA6

Wait, what?!? Your 12V was just replaced 2 days ago, and it's already failed???

 

[DeepBlueMN]

So M3 Performance is 3yrs old now, tesla mobile proactively replaced my 12V for free on Wednesday (2 days ago) - I wake up this morning to leave, I cannot unplug the charging port, I walk around whole car to unlock the door, nothing. On the APP it connects to car and say I have unlocked the doors, nada, I click open frunk and trunk, app shows I've opened, but in reality nothing on the car opens, it sits there just off/dead. Somehow the only APP control that worked is the Vent Windows button, which only vented the passenger side of car - I got a long stick and clicked the inside door open button on passenger door, and it opened. On the screen I get the 12V error message, still cannot unlock doors or trunk or frunk - I use the emergency frunk open jump start on the fender, and give the 12v a jump for 30 mins, no effect. Inside the car, all drivers side open door buttons/mirror/window does not work along with the entire steering column, horn, hazards, shift/turn stalks do not work. Only thing that turns on is screen. did the power off reset with roadside on the phone, no luck. Cannot drive car or put in tow mode... - Car battery is full 90% capacity - cannot release charging port not even from screen -

https://imgur.com/mM7wSA6

Tesla accidentally installed a bad 12v battery. Sometimes happens in ICE cars too. But, what is concerning is, with a battery charger (or jumper battery) on the 12v, that should have restored enough of the 12v system to allow windows and doors and charge port to fully work, and should have allowed the main battery to engage to make the car driveable. (except maybe unless the 12v battery was serious shorting out and the car wouldn’t power up for safety reasons).

 

[samp987]

Tesla accidentally installed a bad 12v battery. Sometimes happens in ICE cars too. But, what is concerning is, with a battery charger (or jumper battery) on the 12v, that should have restored enough of the 12v system to allow windows and doors and charge port to fully work, and should have allowed the main battery to engage to make the car driveable. (except maybe unless the 12v battery was serious shorting out and the car wouldn’t power up for safety reasons).

you are correct - they came back out in a few days and put in a new 12v, and wala everything came back to life. Its silly to see a small 12V can brick the entire car...

 

[rrolsbe]

Tesla accidentally installed a bad 12v battery. Sometimes happens in ICE cars too. But, what is concerning is, with a battery charger (or jumper battery) on the 12v, that should have restored enough of the 12v system to allow windows and doors and charge port to fully work, and should have allowed the main battery to engage to make the car driveable. (except maybe unless the 12v battery was serious shorting out and the car wouldn’t power up for safety reasons).

You are correct. If there was enough 12V power to operate the display, I would have thought the contactors would have closed? With the contactors closed, the DC-to-DC converter should supply the 12V power and the 12V battery would not even need to be connected (or at least that is how it worked about a year ago when I tested). If the 12V battery had a shorted cell, that could keep the jump starter/DC-to-DC converter from supplying enough voltage/current to close the contactors. With the negative terminal cable disconnected from the battery the jump starter should close the contactors and the car should be operational except for an error message indicating the 12V battery is not connected (which of course would be correct).

 

[sodakar]

8/2018 AWD Model 3 here, and after 38 months of trouble-free ownership, I just woke up to a completely unresponsive car. I restarted BT, app, phone, car-shaped keyfob, card key, but no go.

My jumper was in the trunk (fail), so had to call roadside assistance. They applied power to the bumper leads, got the frunk open, but even with power applied to the 12V battery, the car would not start, be it on its own, or with the encouragement of 2-button and/or 2-button + brake pedal.

The service center says they have no mobile battery install option for the foreseeable future, so they want to bring the car in for a tow. Odd that they don’t have something like a mobile battery swap in a major metropolitan area.

Granted, the tow is only 20 miles, but I can’t help but wonder if I couldn’t just swap the battery myself with a new one, or if the jumper cables applied to the battery should have counted towards that scenario and this is beyond swapping a battery.

I did not try disconnecting + connecting the main battery under the rear passenger seat. Should I have tried that?

 

[DeepBlueMN]

8/2018 AWD Model 3 here, and after 38 months of trouble-free ownership, I just woke up to a completely unresponsive car. I restarted BT, app, phone, car-shaped keyfob, card key, but no go.

My jumper was in the trunk (fail), so had to call roadside assistance. They applied power to the bumper leads, got the frunk open, but even with power applied to the 12V battery, the car would not start, be it on its own, or with the encouragement of 2-button and/or 2-button + brake pedal.

The service center says they have no mobile battery install option for the foreseeable future, so they want to bring the car in for a tow. Odd that they don’t have something like a mobile battery swap in a major metropolitan area.

Granted, the tow is only 20 miles, but I can’t help but wonder if I couldn’t just swap the battery myself with a new one, or if the jumper cables applied to the battery should have counted towards that scenario and this is beyond swapping a battery.

I did not try disconnecting + connecting the main battery under the rear passenger seat. Should I have tried that?

Probably should have tried the “negative battery terminal removal” trick mentioned in the previous post… That would have been really interesting to see.

 

[AlanSubie4Life]

Probably should have tried the “negative battery terminal removal” trick mentioned in the previous post… That would have been really interesting to see.

but I can’t help but wonder if I couldn’t just swap the battery myself with a new one,

Second the recommendation to try to disconnect the negative battery terminal. Leave it in Sentry mode always, until you get a new battery, if this works.

 

[sodakar]

Re-reading the post about removing the negative terminal, I see the goal is to remove the potentially defective battery from the equation.

So…. I would:

1. remove the car’s negative cable from the battery terminal
2. connect the negative end of the portable jumper to the negative cable (removed from battery)
3. connect the positive end of the portable jumper to the positive cable (still attached to the battery)

If this works, then I should just go walk down the street and pick up a new battery and swap it.

Not only will this spare a lot of logistical headache for family/work, it would allow me to avoid a potentially nightmare scenario of them trying to tow my car out of a super tight garage with 2” of clearance on either side…

Thank you for your input!

Edit: Or…. If it powers up, I could just back it out of the garage to avoid vehicle and property damage from a super challenging tow, but still opt to get it towed to the dealer and have them look at the car in case it mysteriously died from something other than the battery. If I get it towed, it would certainly reduce the chances of it dying on the freeway and stranding me to zero.

Edit2: I did see posts from other folks who got their Model 3 mid-2018, and possibly a reference to a TSB, but don't think I saw a TSB link... would be super curious if I'm part of the bad batch of batteries. (AtlasBX 85B24LS 1129182-00-B, manufactured 2018/07/11)

Edit3: None of my local stores carry this battery, at least according to their websites (Napa, O'Reilley, AutoZone). That seems... quite strange... But I did find this gem of a post in another thread, so I'll ponder life a bit, since I don't want Tesla giving me grief about the battery swap if all I want to do is back it out of the garage...

What I would do in this situation: Look for a 51R battery at a local auto parts store, and I would not get AGM if I could avoid it to keep cost down. Put it in. And then get Tesla to order an ($85) replacement battery for me and let me know when it's in. It's covered by warranty. Interesting that they say that replacing the battery would void the warranty (seems very dubious unless it damages the car, which I don't think it will - are all the Ohmmu people voiding their warranties?).

You'll be stuck with the generic 51R battery cost ($100-$200?), but maybe you can sell it used and get half the cost back (with a recent receipt and explanation you might get more)? Or you can donate it to another Tesla owner who needs a battery but can't get one, lol.
-AlanSubie4Life

 

[sodakar]

Update: used a portable jumper and jumped it with the negative cable disconnected from the battery terminal, and it instantly powered up.
Thank you for the timely and excellent suggestions.

I see there are plenty of options for obtaining a 51R locally, which is fantastic. Unless the service center vehemently insists I get it towed tomorrow, I would greatly prefer to purchase a 51R battery, and visit the service center without a tow, and preferably when they can do a same-day swap.

Better yet, now that we have shown the issue to be isolated to the battery, perhaps they would consider a mobile services battery swap, as that would be far more convenient than having to drive to the service center. I'm still miffed as to why the battery swap isn't something mobile services can handle any more, as they clearly did them before.

Thanks again for the help!

 

[AlanSubie4Life]

I see there are plenty of options for obtaining a 51R locally, which is fantastic

The 51R available tend to be very expensive compared to the Tesla battery. And who knows if the vent tube will be compatible. I’d see if Tesla could just drop by with one. It is crazy that they would not do such a thing with mobile service!
Glad it worked out for you, and sounds like the portable (lithium?) jumper worked too! Now you can leave Sentry Mode on permanently if you have to drive for some reason (should make it unnecessary to jump the car again). But yes it is probably best to have the battery replaced before driving around, just to be safe.

The post of my you quoted above would only be something I would attempt if there were literally no replacement Tesla/Atlas batteries available…since you’d really have no choice but to get an AGM 51R probably. Hopefully the service centers have the standard replacement batteries though.

 

[sodakar]

The portable (Li-ion) jumper worked, and I don't think it took much -- didn't even drain it 5%. I suppose turning on the main computer requires less power than cranking an ICE.

Silly question... After jumping it via the detached negative terminal workaround, did you folks re-attach the negative cable back onto the bad battery while the car was running? I left the negative cable detached, since my intent was to shut down the car via the screen (which I did), but perhaps because I failed to close one of the doors all the way, I woke up to the car still on, with the negative cable still detached.

The generic Group 51Rs that are within a few miles cost $179, while the one at Costco Interstate one is $99. Too bad I can't figure out where the vent hose location is on any of them just from looking on-line. I agree that a replacement Tesla battery delivered to my home would be ideal, but things aren't looking great on that front.

• The roadside assistance dispatcher I spoke to yesterday claims that mobile service is not offering battery swaps at all for the foreseeable future
• The earliest appointment for mobile services is 10/25, but even then, I'm not sure they offer battery swaps
• The existing in-app ticket with the local dealer has had zero replies to my multiple inquiries in the last 5+ hours since they opened

Sounds like my options are:

1. power on the car, pull it out of the garage, get it towed, figure out how to get myself to the service center to get my courtesy rental car (tow trucks not offering rides during cv19), or pay $200+ for a rental out-of-pocket with no firm ETA.
2. go buy a Group 51R battery for $100+, use the car for my regular commute, and have mobile service swap out the battery next week (if they even offer the service)
3. go buy a Group 51R battery for $100+, use the car for my regular commute, and drop off the car on Saturday when I have time and leave with the courtesy rental
4. drive 20 miles to the dealer on the bad battery (probably don't want to do this)

Admittedly, these options are more about my personal life vs it being a pure battery tech discussion, but I'm including it here just to illustrate how much of a failure it is that they don't offer same-day battery swap services, or the ability to get a rental locally and be reimbursed later, and the only option I have is to tow the car and be left without a car. (well, to be fair, maybe they offer the option to rent locally, but I wouldn't know, as it's hour 6 of being ignored by the service center)

I'll probably get the battery locally and set my bets on options #2 or #3, depending on what the mobile service folks have to say.

Thanks a bunch for the tips!

 

[AlanSubie4Life]

I left the negative cable detached, since my intent was to shut down the car via the screen (which I did), but perhaps because I failed to close one of the doors all the way, I woke up to the car still on, with the negative cable still detached.

The car can detect when the 12V is missing, and since it is unrecoverable to shut down in that state, it probably leaves the car in idle mode permanently when the 12V is missing (this would be good, though would lead to very high standby drain - something like 15-20 miles per day).

Just a guess on my part. Powering down the car via the screen does nothing, AFAIK (except turn off the screen and perhaps go into a "pre-sleep" state). It definitely doesn't open up the contactors (the unrecoverable step).

just to illustrate how much of a failure it is that they don't offer same-day battery swap services,

Yeah, that's crazy. Though this may be due to disrupted supply chains.

figure out how to get myself to the service center

So it sounds like the service center is not very far from you. Have you attempted to get in contact with them (this can be difficult!) to see if they have spare batteries (about $85) in stock? It sounds like maybe Mobile Service is not offering them due to a shortage, but who knows. The easiest solution if the Service Center is nearby is to go get the OEM battery and install it yourself. Whether you drive the Tesla or a different car doesn't really matter (I'd suggest a different one, because why risk it if you don't need to). I guess if I had no other vehicle I'd just drive the 20 miles in the Tesla and do some contingency planning (make sure I have my Lithium battery pack and I can open the frunk with it!).

Tesla does allow you to install the new battery yourself, of course. If your car is still under warranty, it's possible that the cost can only be recovered by having them do the replacement. But for $85...it may not be worth the hassle.

The batteries are probably all stuck on a boat in the waters off the Port of LA.

 

[miimura]

Personally, I would try to charge the bad battery with my NOCO charger while it's still disconnected from the car. If it looks like it does charge up normally, then I would re-connect it and just drive to the service center, bringing my own tools so I could change it in their parking lot.

 

[Cares]

Tesla says a software update was supposed to provide advanced warning of the 12V about to go bad. My first one went bad about 3 years from the date of ownership. About 40k miles. I figured maybe there was a bug in the software and it didn't notify me. I was stranded and had to get towed and Uber everywhere for a day.

Well fast forward a bit and my other Model 3 also had the 12V unexpectedly go bad and not warn me. Also almost exactly 3 years to the date and 39k miles. Once again I had to wait for a tow and go through this whole process.

Is anyone else not getting 12V warnings and having the battery go bad?

 

[Tam]

Is anyone else not getting 12V warnings and having the battery go bad?

My Tesla Model 3 12V battery also died without warning after 2 years 20,000 Miles in 2020. It had to be towed too for a replacement and has been working fine for the past 1 year.

I guess a preventive replacement should be every 2 years before it dies without any warning.

 

[Cares]

2 year even 3 year replacement seems way too fast for a 12V go bad.

 

[sodakar]

AlanSubie4Life said:
The car can detect when the 12V is missing, and since it is unrecoverable to shut down in that state, it probably leaves the car in idle mode permanently when the 12V is missing (this would be good, though would lead to very high standby drain - something like 15-20 miles per day).

Definitely seeing this, but if I have one thing going for me, it's that it's in the garage, with a charge plug, haha.

AlanSubie4Life said:
Just a guess on my part. Powering down the car via the screen does nothing, AFAIK (except turn off the screen and perhaps go into a "pre-sleep" state). It definitely doesn't open up the contactors (the unrecoverable step).

Sure enough, the car does not power down, and to your point, especially with the battery disconnected, it probably won't power down short of me pulling the header.

AlanSubie4Life said:
So it sounds like the service center is not very far from you. Have you attempted to get in contact with them (this can be difficult!) to see if they have spare batteries (about $85) in stock? It sounds like maybe Mobile Service is not offering them due to a shortage, but who knows. The easiest solution if the Service Center is nearby is to go get the OEM battery and install it yourself. Whether you drive the Tesla or a different car doesn't really matter (I'd suggest a different one, because why risk it if you don't need to).

I greatly appreciate the time you're spending on this with me, and yes, it's pretty wild to be in a situation where all I need is a part and a 10mm, but unable to sort it out locally due to the part only being available at the service center. They ignored my app-based messages for 8 hours straight today, so I got off work early and got a ride before their service department closed, only to find their parts department closed at 4pm. I will try again tomorrow...

AlanSubie4Life said:
I guess if I had no other vehicle I'd just drive the 20 miles in the Tesla and do some contingency planning (make sure I have my Lithium battery pack and I can open the frunk with it!).

miimura said:
Personally, I would try to charge the bad battery with my NOCO charger while it's still disconnected from the car. If it looks like it does charge up normally, then I would re-connect it and just drive to the service center, bringing my own tools so I could change it in their parking lot.

I was super tempted to do this, and if I wasn't dealing with logistics to get a ride, I could've gotten there before 4pm. Alas. I appreciate the insightful comments and encouraging words.

@miimura -- a NOCO would've been a great investment both to charge and detect a bad battery. It sounds like even the base model ($30) would help with a trickle charge and bad battery detection, but is there a specific model that you would consider a best buy?

Cheers,

(Edit: formatting)

 

[AlanSubie4Life]

I was super tempted to do this, and if I wasn't dealing with logistics to get a ride, I could've gotten there before 4pm. Alas.

There's always tomorrow. I think I would just drive your own car. My understanding (and again, it is not based on personal experience, so YMMV! - obviously there is perhaps some increased risk of disablement) is that the car will work just fine without any 12V battery. It will just complain about it.

There's really no reason for the 12V after it bootstraps the contactor closure & DC-DC converter power up, as I understand it, because then the DC-DC is providing the 12V for all the components that need it...