TirithRR wrote:
Mr. Broder strikes back. His explanation for the speed differences is? The car has 19 inch all season tires, not 21 inch summer tires like specified. For now I'm calling BS on that one. Now sure, if the tires were really the wrong size for how the car was configured the actual vehicle speed would be less than what was reported. But I'm pretty sure it would still report to the vehicle operator what it thought the speed was, meaning if the vehicle was recording 54MPH instead of the 45, then the operator would see 54MPH on the speedometer, not 45.
Yeah. First off, the difference in MPH between 19 and 21 inch tires is maybe one or two mph at speed. It's not enough to get a speeding ticket if you've increased the size of the tires, something folks on car sites discuss all the time. Also, as you correctly point out, the reason tire difference affects things is because the cars sensors count the number of rotations of the wheel in a given length of time and calculate the MPH from that. So if you increase the diameter of the tire, the same number of rotations will represent a slightly greater total distance. This will cause the speedometer to report a slightly lower speed if you're driving larger tires than the speedometer was calibrated for. So even if we assume that they delivered the car with 19" tires instead of 21", and they didn't recalibrate the speedometer, that means that the speedometer would read slightly higher than the actual speed of the car.
But, as you say, the car would use that as the number to report (what other number could it use?). The speed he sees on the speedometer should be the exact same speed Tesla's data is based on *and* the same speed the computer will use to calculate range based on remaining charge. In other words, it should make absolutely no difference at all to anything.
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Goes on to say that the logs show he did have to turn the heat down (from 72-74 down to 64 at one time). But that's hardly frozen feet and white knuckle temperature.
Yeah. His original article fairly drips with exaggeration. Which is part of why I kinda side with Tesla on this one. If the author had come off a bit less obviously "thrilled" at how poorly the car performed, I might have taken his account with a bit more seriousness.
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And the damning part at the end where he supposedly lost battery charge completely because he took a 50 mile with a 30 mile charge? They told him he could!
According to him, of course. The question is whether or not the Tesla folks could get information about the car while it was operating, or just after the fact. If they were depending on him to tell them what was going on, it would have been quite easy to manipulate the conversation to make it appear like they told him to go ahead with a 60 mile trip on a 30 mile range. From reading even his account, they told him to charge it for an hour and that should recover the lost charge. But the interesting thing is that looking at the data, he never charged the car all the way up to begin with. So he's reporting to them that he charged the car fully, but then some magic happened in the cold that caused it to report a lower charge, so they think "it's charged, but just not reading a full charge for some reason", and give him those instructions.
But if he intentionally just didn't charge the car all the way up, but told them he did, he could get exactly the results reported. Obviously, I can't assume that this happened, but some of the stuff he reported just seemed strange. Now maybe there was some major malfunction with the battery system in that car. But if that's the case, it should have read differently. I'm not an expert on those kinds of battery charging systems, but basic understanding of batteries and how you read charge on them would suggest that a "full charge" is based on relative capacitance within the batter itself (how much it's got relative to how much it can hold to put it simply). That's how all battery charging systems know when the battery is "full". So even if the battery was failing somehow, the charging system should have reported a full charge.
What should have happened was he'd see a full charge, but only a short range reported (indicating an obviously busted battery). What he claimed happened is that he charged it to full (a fact not corroborated by the data), but then it somehow lost its charge and reported a lower charge *and* range later. We can speculate some undefined error that could have caused this *or* we can go with the far more obvious assumption that he just didn't charge the thing up all the way, but claimed he did. The fact that the cars system seemed to be somewhat accurately reporting relative charge status and range potential, it suggests that the battery system was working properly and the latter explanation seems more likely.
Dunno, coming from a computer support background, his whole account reminds me of folks who did something to make their computers break, but want to blame it on the computer instead of themselves, but don't actually know enough about the technology to lie correctly about it. It's really really obvious when people do this, but they don't realize it. I mean, I suppose there is a possibility something when bizarrely wrong with that car, but it does seem like an amazing coincidence that this seems to only have happened to him, and just while driving this one test.
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While many of the faults that occurred during the trip were the result of the Tesla being an Electrical Vehicle, they were not really faults of the design of the car, they were faults in the way the user treated the vehicle. I wouldn't try to take my car on a 50 mile trip with only a gallon of gas available in the tank, even if someone from Chrysler told me it'd be enough.
Yeah. Can't say for sure what happened with that, but I'm still going to go with him just not actually charging the thing all the way up like he was supposed to. It's interesting that on that trip he *never* actually charged the thing fully and there's no indication that it was charged fully, but then later lost charge (something which should be present in the data) like he claimed. To me, that's the most damning piece of information. Again, I'm not completely discounting the possibility of some failure of the car itself, but it really does look like it was mostly his own actions that caused this.