I have heard that all cell phones in the US can be used to dial 911 even if you do not have cell phone service. In other words, if you do not need a cell phone except for dire emergencies, you can just throw any old phone in your car and it will get you emergency services as long as the battery is charged.
Well, if your cell phone is not connected with an established service provider, how can it work to call any number, let alone 911?
FWIW, I have a cell phone that is currently not connected to an established service provider. The battery is good. I just dialled 911. I might as well have used a landline phone where the line cord isn’t plugged in because the result was the same.
Every cell phone subscriber pays about 50 cents a month to subsidize the 911 service, so any cell phone active or not will dial 911. Some local battered womens organizations do a yearly or bi yearly drive to donate old cell phones , so that they can take advantage of the service , in my area.
When I got my latest phone it came with a default SIM card which could be used to dial 911 if necessary. When I brought it in to be activated they replaced it with a new SIM card. It’s pretty difficult to get a phone without a SIM card these days unless you’re getting it secondhand.
When processing a land-line E911 call, the telephone switch sends an ALI and ANI to the nearest PSAP. I can see where a cell phone would have an ANI, but how about the ALI?
ANI = automatic number identifier (the phone number of the E911 caller, like caller-id)
ALI = automatic location identifier (the address of where the land-line phone is installed)
PSAP = public service answering point (emergency dispatch office)
There have been problems in the past with completing 911 calls from cell phones under certain circumstances. These involve things like being in an area without coverage from the subscriber’s provider, lack of roaming agreements, inability of the phone to select a carrier that does have coverage, improper programming of phones.
I know you said that the call didn’t go through, but I think it’s a bad idea to call 911 just to see if you can. This is one of the ways the system gets overloaded.
Well, your case is different. I was adressing someone else. To make it a general announcement: You need a phone capable of functioning. If you phone doesn’t work without “X”, then you need “X” to test the 911 service.
I would have thought that all GSM phones could do this… My old nokia could, and my newer motorola can too. When I start it up with no SIM then it says, “insert SIM” or whatever until I try to dial a 9 then it lets me dial 911, it also works with 112, which is the 911 of some other countries.
I have two different model Nokia cell phones and one SIM card I swap between them. One of them will not function at all without a SIM card. The other (older but more expensive) one will dial 911 without a SIM. I’ve never bothered to work out the logistics of keeping a spare charged phone in the car at all times.