(I skipped some posts on the thread, so my apologies if this is repetitive).
Phone: Google Pixel XL, Android 9.0
Car: Model 3 LR RWD
What I've noticed is that unless my phone is unlocked, the car usually doesn't pick it up quickly at all. So I typically pull my phone out of my pocket, and unlock it (fortunately I'm using the fingerprint sensor for this, so it's at least pretty quick). Then, about 80-90% of the time, the car will see the phone immediately. My wife's phone (a BlackBerry Android-based device) has more trouble than my Pixel though. I haven't done much diagnosis with it yet to see if the same "solutions" work for it as do for mine.
I've also noticed that the Tesla app on the phone may show "Connected" under the key section, and the car may still not recognize it (at least for some time). And, as others have said, sometimes you have to wait (especially if you walk away and come back quickly).
I've also noticed other strange issues as follows:
- I can unlock the trunk, then walk to the drivers door and look like an idiot holding the handle for 10-25 seconds, or until I get my phone out -- I have verified that I cannot unlock the trunk without the phone though -- so clearly the car is detecting it correctly for the trunk, but not the driver's door.
- Sometimes I can unlock the door using the phone (either by proximity, or explicitly using the BT connection, not the cellular data connection), and then I cannot start the car until I mess with the phone and the car for 10-30 seconds. (The car prompts for key card).
I also strongly suspect that while the phone is locked, it's not sending the BLE (Bluetooth Low Energy) "pings" to the car -- and hence when I unlock the phone, it "wakes up" and sends pings almost immediately. I have not made any attempt to verify this technically, but that is my suspicion.
I haven't had the time yet to start documenting all this properly, and then harassing Tesla for hours (or more like waiting on hold for hours to talk to someone who knows mostly less about the car than I do, but has minimal access to diagnostic logs, that largely don't tell them enough) to get it looked at in more detail.
I do always carry my card in my pocket just in case...although fortunately I rarely have to use it (although sometimes I use it out of frustration and to avoid getting my phone out, like when it's raining).