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Jays200
Member
Cool.
Nearly 500 posts for a car with a dead 12v battery.
Won't be the first or the last at least until Model Y gets rid of the 12v battery all together.
Nearly 500 posts for a car with a dead 12v battery.
Won't be the first or the last at least until Model Y gets rid of the 12v battery all together.
ℬête Noire
Active Member
First reaction: Holy crap, how did he get that huge divot in the hood!!!!
Closer look: Oh, that's just a weird reflection of a double-headed utility light fixture.
Third thought: Did I remember to book my yearly optometrist appointment?
Well, to be fair it was determined to be a firmware error that caused the dead 12V, so that is pretty unique in the history of automobiles.
I posted earlier, but it turns out there was a firmware error that either depleted the 12V or prevented the 12V from charging. They updated my firmware and monitored the 12V. All seems to be fine.
To be honest, the verbal explaination was more detailed but I’m attaching the relevant notes.
Thank you. That's excellent news! And it means mine will have a later firmware that won't have the same issue.
Don TLR
Active Member
jstack6
Member
another dirty secret is it's a 100 year old tech Lead Acid starter battery. The DC-DC from the main pack should have and now does keep it charged up but it's still lead acid.
I use a Lithium starter battery in my 2012 S 85 ,3 year warranty too. https://www.element3batteries.com/batteries
I use a Lithium starter battery in my 2012 S 85 ,3 year warranty too. https://www.element3batteries.com/batteries
longshadows
Member
dhrivnak
Active Member
FlyF4
Son of a MX
Mark, after reading through a substantial number of postings on this thread, you are my kind of guy...... cool, calm, and rational. A lot of people in this situation would be screaming, threatening, etc. You seem to understand that in the world of high technology, the old saying of "S___ Happens". Things break. It isn't a perfect world. Yes we pay a ton of money for a car and expect to work perfectly, but that is not the real word. In my experience, acting as you did is the best approach to getting a solution without dying of a heart attack from the stress and high blood pressure it may cause
I'm impressed with the way you handled this situation and the reporting of it.On the other side of the coin, I am not surprised at the large number of postings making a big deal about the simple word of "bricking". I also come from a background in electronic and software engineering. I knew what you meant, so I won't make it a federal crime that you use the word in a context not exactly as what I would describe. I can't understand why people are so picky and quick to correct someone on such a minor issue. It almost takes over this thread. I think I will start using the "B" word every time I have a simple problem with my X just to tick off the picky posters
well not really, but I feel that way.
claudelaval
Member
Same thing happen to me a month ago on my 2017 MS. They keep the car from wednesday to monday while they give me a 100D.No complaint on my part!
Sorry to hear about your trouble MarkS22.
As far as I know the only cars that have been 'bricked' have been the high voltage battery with the original Roadster, due to not having the car plugged in sufficiently in very cold weather - something that is actually quite rare, and doesn't occur often if at all with later Tesla models.
Your High-Voltage battery charger appears to be working - the question is why did the computer systems shut down the HV/LV dc-converter (the 'alternator replacement'). You would have thought this 'simple' issue would be easily addressed and its a wonder that it hadn't been caught in 'pre-testing' of the vehicle generally. Of course, the simplest way to implement this function WOULD have been a relay which turns on the HV voltage to the converter whenever the car was either 'ignition on' (so to speak) OR when it sensed the HV battery was being charged. That way, the thing would just intrinsically work.
One thing that was a bit disconcerting with the 2011 Roadster's system is that the meager dc/dc converter did not have a built in 'current limit' as all car charging systems ( 6 volt and later 12 volt) have had since the Late 1920's. They compensated for that by having the computer disconnect the accessory jack, turn off the vacuum (power brake) pump and turn off the cabin fan whenever heavy loads such as the Anti-lock brake pulser motor had to run. The somewhat faulty thinking there was, if the 12 volt motorcycle battery was either discharged or developed a dead cell, the battery would drain electricity the computer wasn't aware of - a problem 'semi sovled' by monitoring the battery (current) lead on my Volt and Bolt. But all of that 'excessive concern' could have been addressed by simply having the dc/dc converter be current limited (as cars always have been for almost 100 years), and the thing would just work - no computer assistance needed. In that case, the temporary deficiency would simply be met by the battery, and it would go back to being trickle charged presently.
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Mark, the 12 volt battery HAS TO charge off the main battery - as a for instance when you are on a long, low speed trip with the cabin fan, headlights, wipers, radio, etc on. Otherwise, the car would go dead while driving and there would be no facility whatsoever to recharge the 12 volt battery. The battery is hooked up in parallel with the other 12 volt loads - so called 'float charging'.
May have a misunderstanding regarding the question:
Car running: DC-DC provides current: Yes
Car off bulk charging: DC-DC is charging battery: Yes
Trickle charging: DC-DC supplying power to vehicle-off loads, and float charge to battery: Possibly
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