Finding Holes in Tesla's Data, <em>New York Times</em> Assertions



Tesla’s late-night data dump might have refuted some of the claims surrounding John Broder’s ill-fated drive in the Tesla Model S. But there are still questions for both the automaker and The New York Times.


To begin with, there’s one massive chunk of the data missing from the puzzle: GPS. According to a Tesla spokeswoman, the automaker didn’t have GPS data turned on in the car, which makes Tesla’s claims that Broder drove around in circle in a Supercharger parking lot dubious, at best.


But Broder doesn’t help the matter, admitting to the Daily Intelligencer (via New York Magazine) that, “I was circling the parking lot in the service plaza looking for the unmarked and unlighted Supercharger port in the dark. I was not trying to drain the battery.” He repeated this claim to the San Jose Mercury News, saying “I was looking for the charger, which is not well labeled or lighted.” However, this was the second time Broder had been to the Newark Supercharger station, so why was it hard to find?


Tesla also claims that the State of Charge indicator never reached zero. But Elon Musk didn’t need to delve deep into the car’s logs to determine that. The Model S is incapable of reaching a zero charge. The controllers connected to the lithium-ion battery packs won’t let the charge be completely depleted as that would “brick” the battery, rendering it useless. There always has to be some kind of energy stored in the packs to avoid damaging the battery.


That makes the small residual charge in the battery a meaningless technicality, not a smoking gun. Broder, seeing an ominous “car is shutting down” indicator on the instrument panel, assumed he was completely out of juice and did what any thinking individual would do: He pulled off the road, stopped and shut the vehicle down. Unfortunately, there wasn’t enough charge in the high-voltage pack to continue powering the 12-volt accessories, which includes the parking brake, meaning the Model S was immobile and unable to be driven onto the flatbed.



Tesla also claims that Broder never completely charged the battery pack, including the first Supercharger stop where the vehicle told him the charge was complete, despite only being at 90 percent capacity.


This mistake is fully on Tesla, as the automaker didn’t instruct Broder to enable Max Range mode, freeing up an additional 20-plus miles of range and allowing the battery to be fully charged. Tesla doesn’t suggest using Max Range mode on a normal basis as it contributes to more wear and tear on the battery, but this would be the perfect use case for the feature.


Tesla also suggests that Broder didn’t turn down the interior temperature during the trip, but the chart it released last night shows a dip in the climate control temp from 225 to 300 miles. It might not have been exactly when Broder claimed, but he did it nonetheless.




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