According to the Tesla owner’s manual, “Vehicle functions, including some safety systems and opening or closing the doors or windows, may be limited or disabled when installation is in progress and you could damage the vehicle.” Janel chose to heed Tesla’s warning and did not attempt to open her doors or windows during the installation process for fear of damaging her vehicle, but this seems like a very dangerous oversight on Tesla’s part that she was able to be stuck inside at all.
The door mechanisms on the Tesla Model 3 and Model Y are electrically operated, and under normal circumstances are opened from the inside using a simple button to unlatch the door. Should the vehicle have no power, these models do have auxiliary manual cable release levers also found on the door panel, but Tesla warns against using the manual mechanism, citing that it should only be used when the car has no power. Janel said she was aware of this option but didn’t want to risk damaging her car, and she felt confident that she could stick out the heat.
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The Tesla owners manual states that the car will not initiate a software update if Keep Climate mode, Dog Mode, Sentry Mode or Camp Mode are engaged, but it fails to require vehicle occupants to exit the vehicle before the debilitating installation process begins. Tesla also recommends owners install software updates as soon as possible, which could cause some owners to feel obligated to initiate an update in a compromised environment.
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Janel said her car estimated the install would only take 24 minutes, but it actually took 40 minutes, which was long enough for her car’s interior to reach 115 degrees. In a follow-up video, her caption states that she was afraid to mess up her car by getting out during the installation.
So maybe she was not doing the smartest thing by choosing not to damage her car even when it was getting dangerously hot, but considering how expensive Teslas are and how easy it is to violate their EULA, I can't really fault her as much as I fault Tesla.