[rebuilder]

I haven't used any of the services you mention, but an on-line rental service I have used has a simple system: they unlock the car remotely when you start your rental, and the key is in the glove compartment. You may run into issues starting your rental, but lack of connectivity won't stand you in the middle of nowhere.

Is there a particular reason these services can't just leave the keys in the car? Theft?

[squeaky-clean]

ZipCar has keys in the car and it's part of the service rules that the key CANNOT LEAVE THE CAR. I have no idea if they use rfid or something to check, but I felt it was really clear in their "how to use" videos that the keys never leave the car, you can can get banned from ZipCar.

So while there are keys in the car that you could have held onto to use during a cell service outage, you're told to never remove them from the vehicle.

[parliament32]

That's pretty dumb. Car2go (Vancouver) has keys in the glovebox in a special holder-device: you're free to take the keys with you if you want to keep paying for the car as it's parked, but it won't let you "end session" or whatever unless the keys are replaced into the holder thingy.

This also avoids some of the problems mentioned in the above article. I assume they have a remote-kill but unless there's a serious problem, you always have the keys so you can always start the car.

[isostatic]

If the car has no signal, how is it unlocked?

[rebuilder]

That's a problem when starting the rental and returning the car. Pickup points should be placed in areas with good reception. But in any case, not being able to start a rental is a nuisance. Not being able to use the car once you've driven it somewhere is potentially dangerous. I don't see why the car should need a connection to unlock once the rental has been started.

[cbcoutinho]

In the Netherlands, we have Greenwheels, which in addition to being accessible using an app, also allows you to open the car with an NFC-enabled card (I'm assuming for the case where my phone doesn't have reception?). If the car doesn't have reception either then I'm not sure you would be able to open it.

EDIT: Actually, after you pick up the car and start driving it, you (un)lock the car using the keys that are in the glovebox. In principle, you should be able to drive into dead zones without an issue

[oh_sigh]

They could give your phone a signed token indicating your rental times, and then let your phone directly connect to the car to hand it off.

Presumably it is easier for a human with a phone to move to a location with service than moving a locked car, usually just out of the cave you're in.

[rebuilder]

I just don't see why that complexity is necessary, when you could just give the user the key to the car.

[oh_sigh]

The whole point of zip car is that you aren't reserving it a week in advance and want to wait for a key to be mailed to you.

[rebuilder]

Why can't they just leave the key in the glove compartment? That way, Zipcar only needs to unlock the car remotely when the user starts the rental, and lock the car remotely when the rental ends. In between, the user can use the key. like with every other car.

[technofiend]

Probably to prevent accidentally taking the key. If you've ever used a zipcar, the key is affixed to the steering column. I assume they have an ignition interrupter that requires a proper unlock signal because otherwise stealing one would be matter of jimmying a lock or breaking a window.

[pmontra]

Good question, but if there is no signal how could the previous driver have locked the car? Similar services I'm using don't let me end the rental if there is no signal, simply because either the car or the shop on my phone can't talk with the server.