5 ms·

Why can't the wheels turn after the battery dies?

• sounds 15y ago
  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.
  • sbalea 15y ago
    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.
    • Arelius 15y ago
      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.
      • moe 15y ago
        Unlike a laptop, the Tesla was never designed to be run while plugged in. Which is actually an amusing thought. Perhaps they could ship them with really long extension chords, just enough for a city-commute...
        • jambalaya 15y ago
          How about a driving around a generator :p It would be cool though to have wireless power from beneath the road or something.
          • Arelius 15y ago
            Isn't that basically what a hybrid does? Also, it'd be neat if you could attach to the wires for buses that are in many major cities.
  • MBCook 15y ago
    That seems like something that should really fail open, for exactly those kind of situations.
    • simcop2387 15y ago
      I dunno, that would mean that a bricked roadster on a hill would possibly roll away.
      • DrStalker 15y ago
        Failing open would be bad, a "unscrew this small panel and pull this switch" would be fine. My car is old Saab and there are places to move aside bits of trim to manually operate the sunroof and fuel tank cover if the battery is completely gone.
      • kijin 15y ago
        Whatever happened to good old parking brakes? Sometimes, low-tech is better.
        • simcop2387 15y ago
          They may have them, I'm not rich enough to buy a brick that big. But from what I've noticed in friends and family, most younger people don't even realize they're there. "Isn't that what P is for?". It makes me feel old driving a manual transmission and knowing what all of those things are for.
• joshmlewis 15y ago
  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.
  • toomuchtodo 15y ago
    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.
  • maxerickson 15y ago
    Towing shouldn't be a problem, tow trucks carry dollies that can be manually inserted under tires. It takes like 5 minutes. I guess there are probably some limits on speed and range. There are also flatbed trucks.