This retrofit was carried over from the one from China and if I remember correctly, the Model 3 there launched in 2019 after the harness was already changed. So most likely they simply never developed it for the 2018 cars for that reason. That said, they should have figured it out before launching (same deal with the product picture by their web team).
Off topic but assuming you mean your brother's Model Y with an aftermarket auto trunk kit + kick sensor doesn't work, it could be because yours is wired to VCRIGHT or VCLEFT - which is a permanent live (9v when the car is sleeping, but its enough), and your brother's one is connected to the penthouse 12v under the rear seats.
There is no OEM kick sensor.
So the trunk gateway configuration is one of the few things you actually can change with the consumer facing version of toolbox. So even if the service center won't install it, if you can manage to get the parts and run the wiring yourself, you could probably get it to work.
{"accessId":99,"codeKey":"powerLiftgateType","content":
{"enums":
[{"codeKey":"NOT_INSTALLED","description":"Manual liftgate installed","value":0},
{"codeKey":"TESLA_REV1","description":"Powered liftgate installed","value":1},
{"codeKey":"HUADE_REV1","description":"Discrete Huade power liftgate ECU retrofitted","products":["Model3"],"value":2}]},"
description":"Type of power liftgate hardware installed","products":["Model3","ModelY"]}
I just noticed that Tesla created a new product page with the retrofit button:
Looks like they finally corrected the things that people mentioned upthread on the page at least. That should have been how it was launched, but I guess it's not too late while hopefully not too many 2018 owners were misled or inconvenienced.
Yeah. I know it makes me sound very selfish but I keep checking the store in the hopes that all of these canceled orders would result in me being able to order a kit for my 2020.
