SageBrush
REJECT Fascism
I'm looking forward to the scraps from the LFP pack production
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12v battery issue, Tesla unsatisfactory response
- Thread starter Tjhappel
- Start date
mspohr
Well-Known Member
So you said you replaced the 12v battery. Sounds like it was not done by Tesla and not a Tesla OEM 12v battery? What battery did you use as a replacement? Who did it?Sorry this is a thread bump. I've been having a VCFRONT error on my Tesla Model 3 since early November (VCFront_a180 and VCFRONT_a195) more than 50 errors over that time. While driving, while parked, while charging and most amusingly the car waking in the middle of the night, throwing errors and going back to sleep.
Anyway, long story short, the car has been the the Brooklyn, NY SC 3 times (first time they shrugged, 2nd time they replaced the DC/DC converter, 3rd time they blamed a 3rd party hitch (which I removed) and then when it persisted they asked me to bring it in again (best appointment was 7 weeks out, which was this Monday). In the meantime I replaced the 12v battery (3 weeks ago) out of desperation to see if it would fix the issue - it didn't.
Guess what? Today I get a call from another SC I took it to (I moved house) and then said the new 12v battery was the cause of the issue. What's more, I have to pay for a new Tesla OEM battery otherwise my warranty is voided and they won't investigate further.
I know this is all BS... but for now I am going to go along with things until it's fixed, then think about small claims and having them honor the warranty.
I guess I'm cancelling the solar roof and power wall
That could be the problem.
I just had my 12v battery replaced after 6 years. Tesla did it for $167 plus $17 installation. A good deal.
? You want them to honor the warranty on a non-Tesla 12v battery?
mspohr
Well-Known Member
Wooloomooloo
Member
The problem existed for 2 months before I replaced the battery, as I said originally. The issue is not the battery and never was. However because I changed the battery they immediately said that was the issue. It took me almost 45 mins, a spreadsheet and some videos and photos probing this for them to take another look.
electricar
Member
It is probably wishful thinking, but wouldn't it be nice if the Li-ion battery could be retro-fitted to the older models
mspohr
Well-Known Member
Sounds like an unusual problem. As you said. It's probably not the 12v battery. I've never seen those VCFRONT error messages. Something else might be going on. Maybe a short somewhere?
scottf200
Well-Known Member
What 12v did you put in your Model 3? Ohmmu? https://www.ohmmu.com/product-page/12v-lithium-battery-for-tesla-model-3
Wooloomooloo
Member
A short is very possible - amperage spikes can definitely cause this kind of error. I haven't seen any correlation with driving, bumps or other things where a short might be intermittent, but it's still a candidate.
Wooloomooloo
Member
this sucks and if it were me, I'm suck it up and have them replace the battery with a tesla one. but I would demand that they put in writing that if the problem reoccurs after the battery is replaced that they will refund you for the unnecessary oem battery replacement.
good luck.
Wooloomooloo
Member
My bigger issue, other than paying $130 for the Tesla OEM battery and the $400 I already spent on the LiThium battery, is I know for a fact that this won't solve the issue. So it's an expense to just get back to where I was in December.
I'm replying to the person that's complaining that Teslas doesn't 12V li-ion batteries. I'm telling them that Tesla is coming out with them like he wanted.
scottf200
Well-Known Member
MarsOrBust
Member
As long as the software in your Tesla knows it’s an Li-ion battery it should not be a problem. If you swap out your current battery for Lli-ion on your own the software will treat it like a regular battery and this is when you start running into problems and an approved parts for your vehicle.
I mean what’s the difference between the old battery and this one (lithium ion)?
FalconFour
Member
Noticeably different voltage-response characteristics. Rests at a higher fully-charged voltage vs. lead. Able to output more current and charge at a higher current. LiFe cells also have a dramatically non-linear discharge/recharge voltage curve (they stick at darn near 3.3v pegged throughout their charge and discharge, except at the ends). All of which are characteristically "good" things making it a better battery in every way, except that Tesla's computers and firmware track some characteristics to compare how the "battery that I have" compares to "a good battery" in its behavior. Since the Lithium battery doesn't line up with what's known-good, it can flip out a little.
HOWEVER.
That doesn't appear to be what's happening here at all... at all, at all. Like, VCFRONT faults aren't related to the 12v faults - they're a different message! The 12v faults specifically say, the 12v battery "needs to be replaced soon" on the screen, and it persists forever until the car is fully rebooted (pull 12v and HV comms to power-down, not this placebo "shut down" button crap on the MCU screen, or the MCU two-button reboot).
I've never seen a VCFRONT fault. I beat the hell out of my car, though (oh I do very naughty things with its 12v PCS output), and I also have a lithium battery and I dealt with the "12v needs to be replaced soon" faults until I raised hell about it with Tesla service (via app/service requests and a long and polite phone call talking about these slight differences in voltage characteristics and how to solve them - me telling them, lol). And wouldn't you know it, a couple updates later, the 12v messages are entirely and completely gone - haven't had one pop up in so long, I've forgotten about it and the message is a distant memory.
I'm also a bit pissed that Tesla service is treating Wooloomooloo so badly on this. They're grasping for solutions and playing their usual games of "we can't REALLY tell, but it kinda seems like we should blame the user, because our tools aren't giving good enough answers and nobody here is knowledgeable enough about the system to tell what's really going wrong". Sigh. Honestly, I'd be hitting up Electrified Garage to see if they know more about how to dig out what's actually wrong from the thing's memory.
SageBrush
REJECT Fascism
Is that general consensus, that LFP can now be used in the Model 3 and not cause alerts and refusal to update OTA ? Is it true for a 40 Ahr battery (not the 20 Ahr revised battery that Ohmmu is selling) ?
And since I am in question mode ...
How does the internal resistance of LFP compare to PbA AGM ?
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Excellent deal. Tesla battery replacement it's a difficult thing )
What battery brand they put? OEM or Tesla battery? Is it an AGM battery?
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