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

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Radlaw

Charles
Supporting Member
Dec 29, 2018
412
188
San Diego California
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.
 
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.

Why in the world would you expect the manufacturer to install an aftermarket product for you, when the OEM product is still available from them?
 
everyone is different, but I personally don’t see the benefit of paying the ohmu price when the OEM is so cheap.

I’ll probably proactively replace at 2.5 years if I don’t get a warning before.
Suggest reviewing other posts on this subject. Many have been stranded, in more ways than 1, with the original battery. Apparently this dosen't happen with Ohmmu.
 
Suggest reviewing other posts on this subject. Many have been stranded, in more ways than 1, with the original battery. Apparently this dosen't happen with Ohmmu.

There are tons of threads on this topic, yes. It has also been shown that, you could proactively replace the OEM battery every 2 years, 4 times, before you get to the cost of the Ohmmu battery, so you could have a new battery every 2 years for 8 years, before you get to the cost of that battery.

(OEM 12V = $85, 4 of those = $340, Ohmmu battery = $439)

Thats assuming it lasts that long and also does not have issues over time with tesla changing charging algorithms as they have done twice now, necessitating a response from Ohmmu.

I also understand you basically asking tesla the question "hey will you do this for me" but dont understand the desire to create a thread about them not doing it, as if it should be expected for them to do it.
 
Battery Management System.

Other choices:
Bowel Movement Sensor; needed when the battery system totally shuts down while driving 83MPH on the freeway and the car "freezes"
Body Mass Sensor; sensor in driver's seat which detects presence (or absence) of driver
Barometric Manipulation System; pressurizes cabin interior to keep out unwanted exterior Bovine Meadow Smells
 
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Does the OEM battery Tesla uses also have its own BMS? What is the difference?

No (not the one you are talking about, anyway). I dont know if the brand new Lithium battery that comes in brand new 2022s does, but the $85 dollar one does not have a bms because its a dumb battery and doesnt need one.

For more than that, "suggest reviewing other posts on the subject", which I do not consider being rude, as its the exact same verbiage used earlier. I suggest these , for starters:


 
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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.
In general car dealers will never install aftermarket stuff like that.
 
In general car dealers will never install aftermarket stuff like that.

It kinda depends on what it is. For example, BMW dealers (many of them) were also installers for aftermarket tune kits. The difference there is a dealer is an independent entity, and Tesla is the Manufacturer, not a dealer. People like to use the term interchangeably but this is a situation where there is a real difference.
 
Suggest reviewing other posts on this subject. Many have been stranded, in more ways than 1, with the original battery. Apparently this dosen't happen with Ohmmu.
It will eventually. And the car has even less of a chance of detecting the failure proactively.

Plus, there are batteries that will work from an auto parts store like other cars.

Like other cars, some will stick with OEM. Some will go with cheaper, and some will go with the fancy (like spiral wound AGM battery). I’m just pointing out my decision is to stick with OEM and likely proactively replace at 2.5 years. Mine was last changed Oct 2020.

In general car dealers will never install aftermarket stuff like that.
Especially if one brings it into the dealer and doesn’t purchase from them.
 
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The OEM lead acid battery needs no internal BMS. The cars charging system handles it.

A lithium ion battery needs a BMS to manage the individual cells & to make the car think it’s dealing with a lead acid battery.
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?
 
Becasuse I asked them to. There was a battery cost to them to install their battery; and no battery cost to them to install the battery.

Thats not correct, actually. By installing that battery, they would be endorsing it, and taking on "any and all" issues you would ever have during its operation. You would rightly say "but you installed it, so fix it" if anything at all didnt work properly with it, like firmware updates, false positives, etc. So, their is definitely a cost to them for doing it, which is why they didnt.