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When I Took My Zipcar Into the Wilderness

theatlantic.com

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Re: When I Took My Zipcar Into the Wilderness

#181

Post by mirimir »

jacobush wrote: post #37
mirimir wrote: post #25

Earlier quoted context omitted.

Good point. I should have noted that I've only done that with a 60s VW Bug. Just to see, I have turned off and restarted my ~10 year old Civic, going down a hill. But not with the battery disconnected. Maybe I'll try it. Not now, though. Edit: And upon reflection, maybe not. Because I'd have to pay someone to reset the computer. Edit: But wait a minute. If the vehicle is moving downhill, and you engage the clutch in…

Don’t do it with battery disconnected, it can cause the voltage to go too high and you may fry things. Back in the day only bulbs, nowadays who knows.

Thanks. I'm not going to try it.

Re: When I Took My Zipcar Into the Wilderness

#182

Post by mirimir »

perl4ever wrote: post #83
wolrah wrote: post #20

Earlier quoted context omitted.

> That depends on the vehicle. If it's an ICE with a manual transmission, and you can get it moving fast enough, you can pop the clutch to start it. This depends on just how dead it is on newer cars. If it's able to run the electronics but just unable to crank enough to start, this can work. If it's dead enough that you can't unlock the doors it's probably also dead enough that the fuel pump, ECU, etc. aren't going t…

I don't remember ever having any problem starting my 92 Civic that way. It definitely had EFI and an ECU. I know I started it when the alternator was bad, as well as when the battery was dead. (not at the same time)

My Civic is mid 00s, but I'm pretty optimistic that I could manage it. Hopefully won't need to, though.

Re: When I Took My Zipcar Into the Wilderness

#183

Post by zaarn »

mcguire wrote: post #148
zaarn wrote: post #84

Earlier quoted context omitted.

Car batteries are generally a starter battery (minus EV ones). They don't like being closed circuit for extended periods of time. A low current is usually allowed (200mW is the top end in my experience), but anything over will, over time, sulfinate the plates in the battery and cause it too loose charge and capacity rapidly. Generally if you want to run a low current device on a lead acid battery, you should use a de…

How long does it take to damage the car battery? How long does it take to discharge the car battery?

Depends on the load.

Re: When I Took My Zipcar Into the Wilderness

#184

Post by mirimir »

jotm wrote: post #99
mirimir wrote: post #25

Earlier quoted context omitted.

Good point. I should have noted that I've only done that with a 60s VW Bug. Just to see, I have turned off and restarted my ~10 year old Civic, going down a hill. But not with the battery disconnected. Maybe I'll try it. Not now, though. Edit: And upon reflection, maybe not. Because I'd have to pay someone to reset the computer. Edit: But wait a minute. If the vehicle is moving downhill, and you engage the clutch in…

The alternator needs to get some decent RPM to generate enough power. You'd have to go downhill quite fast.

In first gear, so not that fast.

Re: When I Took My Zipcar Into the Wilderness

#185

Post by parliament32 »

sly010 wrote: post #106
roland35 wrote: post #95

Earlier quoted context omitted.

This sounds like a pretty common scenario for zipcar and certainly cell phone coverage coming in and out is something that they should be planning and designing for! Maybe a series of one-use pass codes or something like that could help. I always make sure there is a failsafe when I have two microcontrollers talking on the same circuit board! Never fully trust anything external.

There are many things they could do with software only without having to change their current scheme. - Use exponential backoff when looking for network (although I find this part of the story hard to believe, my phone survives much longer when there is no network) - Have a larger grace period. Let the key card just work for an extra day or indefinitely if the car's last known location is not the garage. Charge the c…

>my phone survives much longer when there is no network

Interestingly I've had the opposite experience (with a Pixel 2 XL, and before that a Nexus 6P). With both phones, when going on out-of-service hikes the battery drained significantly faster than usual -- despite not using the phone at all, I'd see a 40-50% power drain over ~8 hrs. Putting the phone in airplane mode when I knew I'd be out of service solved the problem, as expected.

Re: When I Took My Zipcar Into the Wilderness

#186

Post by parliament32 »

squeaky-clean wrote: post #117
rebuilder wrote: post #42

Earlier quoted context omitted.

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?

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 fr…

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.

Re: When I Took My Zipcar Into the Wilderness

#187

Post by rolph »

epoch_100 wrote: post #140
anewguy9000 wrote: post #126

Earlier quoted context omitted.

yes if you want to get pedantic the subheadline could more aptly read, "i was unable to open or start a car with a dead battery". or for the main headline, "when i took my non-zipcar into the wilderness (and its battery died and i was stranded)", would anybody read it? no.

A key element here is that the battery likely died _because_ there was no service. When the car's cellular unit is scanning for service, it uses significantly more power than usual—quickly draining the battery.

when you leave your vehicle at a trail head for a few days you can disconnect the battery leads, and greatly increase your chance of coming back to a live battery.

Re: When I Took My Zipcar Into the Wilderness

#188

Post by [deleted] »

squeaky-clean wrote: post #117
rebuilder wrote: post #42

Earlier quoted context omitted.

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?

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 fr…

[deleted]

Re: When I Took My Zipcar Into the Wilderness

#189

Post by roland35 »

parliament32 wrote: post #185
sly010 wrote: post #106

Earlier quoted context omitted.

There are many things they could do with software only without having to change their current scheme. - Use exponential backoff when looking for network (although I find this part of the story hard to believe, my phone survives much longer when there is no network) - Have a larger grace period. Let the key card just work for an extra day or indefinitely if the car's last known location is not the garage. Charge the c…

>my phone survives much longer when there is no network Interestingly I've had the opposite experience (with a Pixel 2 XL, and before that a Nexus 6P). With both phones, when going on out-of-service hikes the battery drained significantly faster than usual -- despite not using the phone at all, I'd see a 40-50% power drain over ~8 hrs. Putting the phone in airplane mode when I knew I'd be out of service solved the pr…

My Pixel 3, on Fi, also seems to heat up quite a bit whenever I am at a bad network location!

Re: When I Took My Zipcar Into the Wilderness

#190

Post by Nextgrid »

fred_is_fred wrote: post #164
lm28469 wrote: post #150

Earlier quoted context omitted.

Never play the "who's dumber" game with private companies you'll always lose. If it happens twice you should switch on your common sense and stop using the service, or at the very least change your behaviour/don't be surprised if you get banned. > which any engineer worth their salt should’ve predicted - this is not rocket science There are probably tons of other issues you don't know about. Making it work offline wo…

Any engineer worth their salt knows that they have 100 things to work on and this guy's corner case didn't make the cut. Easier for them to ban him and work on a new feature that generates revenue for thousands of users.

My point is that this isn’t some minor bug that you can leave in the backlog because it’s just a minor inconvenience. This is a major dealbreaker that should’ve been thought of when designing the service in the first place.
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