I'll say it again. I think Tesla has made a major design error by relying on the tiny 12V battery to start the car.
This quote started off this whole tangent. The first post suggested the 12V batteries were failing due to poor build quality, which would mess up even the best designed system.
It's pretty easy to access the terminals. Just pop off the nose cone.
Maybe a bit harder than than popping the hood, pulling off the engine cover plastic, then the battery cover plastic, but still in the same realm of difficulty of getting to terminals.
Wouldn't you know it, a day after this revelation I get the "12v battery warning - service soon" error when I start the car this morning.
One call to service and 90 minutes later they have a tech at my office to swap the battery. 30 minutes later I'm good to go. Amazing service.
Seems like replacing the battery isn't all that difficult, or time intensive. Not sure if there was a special tool involved. But I can tell you I broke the coolant loop in my GTI changing out the battery, and I also had to go to Sears and buy another socket extension because I needed about 12" worth to get to the nuts to the battery strap in my GTI. Even with all the tools I wouldn't say you could change the GTI battery in less than 30 minutes.
With all the excellent engineering that seems to have gone into this car, is the 12V issue really an easy fix or was the perfect solution not done for cost reasons. Find it hard to believe they made such a design flaw when everything else seems on track (missing software features being added over time excluded).
Exactly, Tesla did this to start. It didn't work well. 12V batteries DO WORK WELL. EVERY CAR MADE HAS ONE TO START THEM!
It is pretty obvious Tesla didn't think through what happens when the battery OR DC-DC converter dies.
I am sure they did. The same thing happens when your 12V dies in ANY OTHER CAR. It wont start. And if your alternator goes, same thing.
Many people have had their 12V battery die with no warning (is that what happened to you, patp?).
A lot of people ARE getting 12V warnings. The only warning I got in my GTI was the windows not all going up at the same time for about a week prior to dead. My wifes Civic gave NO warning at all. She went to work, parked, then came out 4 hours later and dead. New battery and everything has been great for another 3 years.
Taking off the nose cone is not as simple as opening the hood on an ICE. If Tesla's backup is a 12V jump, then the terminals should be made available without taking body panels off. I would also suggest that there are better ways other than external jumps to give you a backup to the 12V battery - such a manually operated contactor relay that powers a DC-DC converter to allow self-jumping. OR, and here's a crazy idea, get rid of the 12V battery entirely since it is a part that routinely fails anyways. The initial Roadsters didn't have them. You CAN engineer an electric car to not need them. It IS possible. Tesla just decided to not do it (to be fair AFAIK other electric car makers have them too, but why can't Tesla be better).
I agree a manually operated contactor could be nice. I don't know how feasible that is. I imagine that it would have to be very large, and might not be easy to close by button press. Tesla DID engineer a car that didn't need a 12V battery. Their FIRST car. But they stopped doing it, probably because having a 12V is a better solution.
But the method of keeping it charged, the size of the battery used, and the location of the terminals so it can be jump started are design decisions. I don't have enough info to determine whether the battery capacity is sufficient for its intended use, and I wouldn't go so far as to call it a flawed design, but I would say it can be improved.
Not saying it can't get better.
I think there is an issue with the design. Like you, I have been stranded also due to a dead battery. Here's the difference though between the Tesla design and most any other car maker's design: The battery is easily consumer replaceable. That means I don't have to wait for someone from Tesla to change out my dead battery, I can choose to do it myself or have it changed by any competent mechanic. That is a huge difference as it means my downtime and when my car is back in service is not dictated by Tesla but rather by me. I have a choice.
Another concern is the battery appears to be outfitted with a circuit that prevents an equivalent battery from being substituted. For a commodity item that needs periodic replacement, that design decision by Tesla means only they can replace the battery. No aftermarket competition = higher costs to the consumer.
I would think it you could get at it. Apparently removing the nose cone isn't all that hard to get to. Sure it isn't as easy at getting at my wife's Civic's battery terminals but it shouldn't be that hard. I'll test it out when I get home.
