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Tesla Won't Install Ohmmu [aftermarket 12v battery]

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Bought a 12V Ohmmu battery. Original 12V battery began failing as evidenced by screen warning. Took my T3 to Tesla repair service shop and asked to install the Ohmmu battery. When finished I looked in car and my new Ohmmu battery was still in original box, uninstalled. Asked service rep about it and he said they couldn't install it because of waranty, and there was no charge for the new OEM battery. Should I replace the new OEM battery with the Ohmmu or just let it go? Maybe, I should sell the Ohmmu battery on eBay, since they are hard to get.
I would put in the Ohmmu and keep the OEM battery as a spare for a while. If the Ohmmu works without problem, sell or repurpose the OEM.
 
Dosen't the car's charging system also handle a Ohmmu lithium battery? It sounds like a battery with a BMS is a good thing. Why does the car need to think it's deaing with a lead acid battery?
In recent software updates, testing of the lead acid battery was added. The testing included an over voltage test of the battery to check health. The Lion batteries BMC would see that and isolate the Lion battery for about 5 minutes. During the isolation, the car would think there was a battery failure and throw off messages. The BMC's job is to protect the Lion battery and cell balance. Lead acids don't need that protection. The latest version from Ohmmu has a BMC that can work with the testing to prevent battery error messages. For benefits of Lion see the Ohmmu site for their test data.
 
In recent software updates, testing of the lead acid battery was added. The testing included an over voltage test of the battery to check health. The Lion batteries BMC would see that and isolate the Lion battery for about 5 minutes. During the isolation, the car would think there was a battery failure and throw off messages. The BMC's job is to protect the Lion battery and cell balance. Lead acids don't need that protection. The latest version from Ohmmu has a BMC that can work with the testing to prevent battery error messages. For benefits of Lion see the Ohmmu site for their test data.
Now that is a good, informative, educational useful answer. Thank you very much.
 
The OEM battery is only 85 dollars? I was going to get a Ohmmu battery when my OEM battery died but for 85 dollars I would just replace it with another OEM battery. I assumed they were 150ish

Its $85 from tesla in southern california. I believe its the same everywhere. The battery itself is $85, and if you pay for tesla to install it, that total cost (tax, everything, "out the door") in SoCal is $128 and change. Its a little different in other places as the labor rate may be different, but fully installed by tesla its $115-130.

Anyone considering installing an aftermarket battery is likely capable of installing the OEM one as well, so they could just pay the $85 and install it themselves.

Note that, There could be other reasons to prefer the Ohmmu. Some people state that audio sounds better. Its lighter (weight) if that matters to you. Its supposed to be longer lasting.

It also has its own BMS (battery management system) and twice so far since 2018 tesla has made "some change or other" to how they interact with the 12V battery that has made the Ohmmu throw false positive errors about status, failing battery. Ohmmu is testing a fix for the second time, now. There is no guarantee that this wont happen again (although Ohmmu has been very supportive to people who have their batteries so far.

There could be reasons to install this or any other third party Lithium ion battery, but PRICE is ABSOLUTELY not one., because as I said you can replace the battery every 2 years 4 times and still not get to the price of the Ohmmu battery. Thats 8 years, and still not "break even" for cost, and there isnt any reason you have to replace it proactively every 2 years, you could do it every 2.5 to 3 years and make it 8-12 years (and still not get to the cost of the ohmmu battery).

If you (or anyone) is considering an aftermarket 12v, do it for something other than cost.
 
Tesla replaced mine for free.
Yeah, I think you mentioned in your first post you got the low voltage battery warning. in this case it's probably treated as a warranty replacement item if you get the warning. A family member had the same experience in February after getting the warning, I had told her she'd have to pay a few hundred for the service, but they did it for free.

This is a bit overlooked in the forums, probably because there's no official or written policy on this, so hard to tell if it's their standard practice or just one-time goodwill. But seems like multiple folks have the same experience.

If you proactively ask them to replace the battery, when there have been no warning or logs, that's when they definitely charge you for it. In my own household, both cars on the original battery at 4 and 5 years respectively , so probably I should pony up for preventative replacement to not risk getting stranded somewhere.

EDIT: I googled around and learned actually quite a number of automakers do include the 12v battery in their new car warranty, some explicitly, some not. I guess I've never had the pleasure of having the 12v go bad during the initial warranty, though many later on. Oddly, when it's explicitly stated in the warranty, they usually say it's covered when "defective", so makes we wonder if there's some criteria for that vs just normal expected life of the original 12v installed.
 
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The latest version from Ohmmu has a BMC that can work with the testing to prevent battery error messages.
I installed a new Ohmmu battery in my MYP on April 30, and after nearly one week of trouble-free operation today I got the error message "Schedule service to replace low voltage battery". Coincidentally today was also the first time since putting in the Ohmmu that a software update tried to install. So I also got the error message "Unable to start the software update because there is an issue related to the 12V battery...." Thanks to someone in this thread for mentioning the Ohmmu petition, I would have missed it because it was buried in my email inbox.
 
So they put a new battery in for free, and you are mad?!?! Ok then..heard it all. Do what you want, your car...but warranty issues will likely be denied from there on out...you've been warned. If this were some other brand and proven car, no issues. but Tesla...who know how they will respond with warranty issues with aftermarket parts. I have coilovers, different wheels/tires and rear trailing arms and they never had an issue, but of course, nothing I had a claim about was due to these parts.
 
The reason I believe this thread to be valid is because there are now starting to be a LARGE number of Teslas out of warranty (like mine).

If they would support garages working on old Teslas that would be one thing, but they really don't. So I have to go to Tesla for everything, so "Here, I bought this on the internet, please install it, I understand you can't warranty it, the manufacturer will"
 
The reason I believe this thread to be valid is because there are now starting to be a LARGE number of Teslas out of warranty (like mine).

If they would support garages working on old Teslas that would be one thing, but they really don't. So I have to go to Tesla for everything, so "Here, I bought this on the internet, please install it, I understand you can't warranty it, the manufacturer will"
At least the service manual is available free and the battery replacement procedure is not difficult but longer than an ICE car. Tesla Service
 
I had my DC disconnect swapped and I didn't realize how many of my 3P additions would be in their way. Got an OBDII computer hanging off the back of my center console, have a power frunk with foot sensor. Glad the center display swivel didn't cause them issues getting the car apart and more importantly back together (other than the frunk kept opening when you closed it so they just unplugged it).
 
Well, I just booked my 12 volt Model S 2016 battery replacement. I have the ‘extended warranty’ but the estimate for this >$300 plus tax. Roadside replacement.

this idea of shutting down all but OEM replacement parts seems to be contrary to the “right to repair” doctrine being adopted around the world.

to deactivate a non-OEM product, just because they can seems to be unfair at least and potentially illegal at best
 
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Well, I just booked my 12 volt Model S 2016 battery replacement. I have the ‘extended warranty’ but the estimate for this >$300 plus tax. Roadside replacement.

this idea of shutting down all but OEM replacement parts seems to be contrary to the “right to repair” doctrine being adopted around the world.

to deactivate a non-OEM product, just because they can seems to be unfair at least and potentially illegal at best

Thats absolutely not what happened here in any of these threads, though.

Changing algorithms so that your battery works better / differently is not the same thing as "shutting down all non oem" batteries. someone can still go buy a non oem lead acid battery.

Its on the third party battery manufacturer to make their product work, not the manufacturer.
 
Well, I just booked my 12 volt Model S 2016 battery replacement. I have the ‘extended warranty’ but the estimate for this >$300 plus tax. Roadside replacement.

this idea of shutting down all but OEM replacement parts seems to be contrary to the “right to repair” doctrine being adopted around the world.

to deactivate a non-OEM product, just because they can seems to be unfair at least and potentially illegal at best
At least on the 3, they didn't deactivate it they changed the charging profile in an attempt to make the lead acid 12 volts last longer causing compatibility issues. On my last test with an Ohmmu, the resting voltage was right about the charge level voltage so the computer freaks after a few hours and locked out charing the Lithium. All of the aftermarket Lithium makers need to get together with Tesla for a solution. Meanwhile, Diehard (a Clarios LLC company) is now making AGM batteries that are specific to EV's. Supposed to last 30% linger than a regular AGM. Look at the AdvanceAuto.com site to see if a battery is available. BTW the Ohmmu site shows a Lithium battery for the model S and no mention of issues like with the 3/Y. They have installation instructions for the DIY.
 
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