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Elsewhere in the thread I calculate the life support draw at 29 watts from available data (53kWh battery, 11 weeks to idle to empty). I think you can afford the $100 if you have a Tesla.
"It's A Brick" - Tesla Motors' Devastating Design Problem
41–50 of 284 posts
Re: "It's A Brick" - Tesla Motors' Devastating Design Problem
#42I've bricked a number of MacBook Pro batteries this way but (A) Scale is obviously different - only $100, and (B) Genius Bar came to the rescue - even though it really was my fault, they covered it under warranty.
Yeah, I've been told it falls under the standard AppleCare warranty if this happens to anyone. (Likewise with fraying of charger cords).
Personally, I don't see why it's "your fault". I've seen it happen many times, all you need to do is let your computer drain completely and leave it for a few days (not months as some people have stated in this post). Although I'm sure it says something about it in the manual somewhere, it's hardly common knowledge that this is something you need to be careful of.
Re: "It's A Brick" - Tesla Motors' Devastating Design Problem
#43"In at least one case, Tesla went even further. The Tesla service manager admitted that, unable to contact an owner by phone, Tesla remotely activated a dying vehicle’s GPS to determine its location and then dispatched Tesla staff to go there. It is not clear if Tesla had obtained this owner’s consent to allow this tracking5, or if the owner is even aware that his vehicle had been tracked. Further, the service manage…
Class action my ass; OnStar can kill a car remotely whether you have the service or not. Why would I be shocked my $109K luxury electric sports car can report its location back with the rest of its remote telemetry?
Re: "It's A Brick" - Tesla Motors' Devastating Design Problem
#44Earlier quoted context omitted.
The article explains that it doesn't have power to turn on "tow mode" - so the wheels remain engaged to the now dead electrical system, effectively locking them in place.
Why can't you plug the car in, and switch on tow mode? Even a laptop with a dead battery works fine when plugged in. I'd venture to say that a tow truck's alternator should be enough to disengage the wheels. Sorry, but this is just crappy engineering.
Unlike a laptop, the Tesla was never designed to be run while plugged in. Combined with the fact that they arent designed to hit zero battery. This is an easy oversight of design, where the laptop can run directly off of wall power not due to fix the problem of a dead battery, but to provide less stress on the battery while being used and plugged in. A usage case that does not exist under normal usage of a tesla.
Additionally. Do we know that it is actually impossible to engage tow mode while plugged in? That still doesn't solve all cases of having to manually move it.
Re: "It's A Brick" - Tesla Motors' Devastating Design Problem
#45Earlier quoted context omitted.
120v @ 15A is 1800 watts. As I said, I was able to measure the wattage being delivered at the end of my 100 foot 16 gauge "home depot" orange extension cord connected to a space heater and found less than 900 watts being delivered to a load that normally pulls 1750. The voltage had also dropped below 100 volts. Its possible that the Tesla simply won't charge at all if the current or voltage on the line becomes too lo…
Er, no, this is probably wrong. The voltage drop is due to resistive losses in the long (and skinny) cable, and the resistive losses depend on current flowing. So, unless there are some weird effects due to the car's electronics, you cannot stop the charging, only slow it down.
So the charger sees the 120 V, decides to begin charging, current flows, and the voltage drops. If the voltage drops out of range, the charger aborts because it's out of design spec and/or there's a significant amount of power being dissipated, probably by resistive heating (i.e., risk of fire).
This is probably necessary to achieve UL rating.
Re: "It's A Brick" - Tesla Motors' Devastating Design Problem
#46Sounds like we got ourselves a great deal for the $400 million the government lent them.
With many of these vehicles in California, I shudder to think how many might brick just because the grid gets broken by an earthquake.
Re: "It's A Brick" - Tesla Motors' Devastating Design Problem
#47Why can't the wheels turn after the battery dies?
It's probably around the same in "normal" cars today. If you just have a car in park it won't move until you move it out of park, the catch is in gas powered cars, even if the battery is dead you should be able to put it in neutral to get it towed. In electric cars when the battery is dead, well that's all you have, so you can't get the gear into neutral to make it at least rollable.
Sounds like a design failure with what little transmission the roadster has, at least with the parking prawl not having some sort of mechanical deactivation.
Elon has a bit more work to do.
Re: "It's A Brick" - Tesla Motors' Devastating Design Problem
#48This is akin to leaving the headlights on when the car is turned off in a regular car. You're asking for trouble. (though not to the tune of $40,000) When the car is turned off, there should be some kind of indication of how long it will take to brick the thing. If that indication is days rather than weeks, it should yell at you. Loudly. At least that way all owners will know of the threat. The car will educate them.…
No, leaving the headlines on on your car is unlikely even to ruin your $100 car battery. You'll just need a jump start.
The two situations are not at all comparable.
Re: "It's A Brick" - Tesla Motors' Devastating Design Problem
#49Could this really not be prevented by a $10 microcontroller and a big-ass relay to just disconnect the battery if it reaches a certain discharge state? Even my iPhone can turn turtle to protect its battery when it gets too low. Also how much power does it take to keep the damn thing plugged in? The article indicates that a 100 foot extension cord isn't enough just to break even and the car discharges even when plugge…
Could this really not be prevented by a $10 microcontroller and a big-ass relay to just disconnect the battery if it reaches a certain discharge state?
Not necessarily. This might help, but the battery will also have self-discharge, meaning that it can lose charge without being connected to any load at all. If you get the charge down low enough, and then wait long enough, then even a full disconnect from the system won't help.
Re: "It's A Brick" - Tesla Motors' Devastating Design Problem
#50[deleted]
"The article indicates that a 100 foot cord connected to a standard outlet does not provide enough power to prevent a Tesla car from discharging..."
Pretty sure they say that to make sure people don't just use any old cord. A 24 AWG cord with 66% voltage drop as the low end would change your cost analysis radically.