The tl;dr - My gripe is that this parlor trick of proximity unlocking should have been back-burner'd for a fob solution that works 99.9% of the time or better (that's once a year for someone getting in and out of their car 3-4 times a day), without workarounds. Or it should've been designed from the beginning with standards and designs that are intended for proximity detection, and not tried to shoehorn that ability onto Bluetooth. I just want to get into the car, sometimes with guests, without any drama, and I want to drive this fantastic machine.
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Needing a Faraday pouch or box, or turning the Bluetooth on and off for the Lucid app, to keep the car's mileage up overnight is a band-aid to a design problem. Having to change the batteries every month or three is a bad design, especially since there are fob solutions that last years between changes. Using the Bluetooth equivalent of RSSI is unlikely to be consistent over all of the use cases a car sees, not to mention 2.4GHz radio congestion, handshake failures, etc. Bluetooth as a standard was never intended for something mission critical like a key. In my case, I've resorted to using both the mobile key and the fob because neither one is fully reliable or consistent in all cases, and I haven't even had to deal with a second profile yet. The fob will let me get in the car and drive off (usually expediently, but not always), but once I'm parked, I get the dreaded "key not detected" error, in spite of brand new batteries. I'll fish it out of my pocket and hold it in the clear air at the center of the car, and it will take 10-15 seconds for it to be recognized. Using the mobile key (iPhone 13 Pro), it's reliable once the vehicle is unlocked, but I consistently have to unlock the phone to unlock the car. This may be an Apple problem, but that makes it a real issue for a big chunk of the customer base. Using the correct key to operate a device should not require thought about whether it's going to work or not. This has been more than a year on now and we're still having this conversation. I don't have faith that a software solution for the current hardware will solve the key problems.
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