iPad 3 Why 3G does not work after being on WiFi

reestr Frankfurt, Germany

Still getting issues, even with replacement hardware. I'll try to re-open my support case with Apple now to see if they can escalate...

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That means that I'm going to be in the same boat. Called apple today and tech told me to do a fresh restore which I did. But I will have to drive to where I will get the extended service in order to see if it worked or not. Like I said in another thread, my 3G/4G connection dies once I step out of my "home" area. The WiFi works great though, no problems with it at all. I guess I had this problem since day one but never noticed it because I've been in my "home" area. Every 3 weeks I have to drive to another city to get chemotherapy and I was there last week; that's when I noticed the problem. Can't return it now where I bought it because my 14 days are over; if I knew this from the beginning I would returned it right away! I guess I will have to wait for the iOS update.

Good to see some coverage in The Register:

http://www.theregister.co.uk/2012/04/06/apple_connectivity_problems/

I am not sure why they are taking this long to acknowledge this known problem. They should at least let us know that they are working on a fix.

Hi,

I have the same issue here in Germany.

After using the iPad in Wifi the 3G seems to be dead. I have to run a reset to get it back running.

It's strange that Apple does not react. They might fear another Antennagate?

Based on the handling of 'antennagate', Apple probably won't announce anything until they have fully investigated the issue. I suspect if its a software bug then they'll just acknowledge it on the day of, or a few days prior to the bug fix release.

I can understand why they would handle it in this respect so not to attract too much bad publicity, but as a customer it would be nice to know that the issue has been recognised by the appropriate Apple engineers and a resolution is being sought. Would save me bothering to swap out my iPad etc. I'll happily sit tight and live out the problem with the knowledge that a fix will soon be available.

Hi,

I just hat a chat with German Support. They still treat it as a single incident. Telling them that there is hundreds of comments on their own site he repeated that they don't knwo this as an epedemic issue.

Knowing a bit about Call Centers I would not be surprised if the (mostly outsourced) call centres are the last in line to inform internally.

He proposed factory reset (I don't like to spend 4 hrs restoring when I see here that it's useless), driving to the next Apple Outlet (also 4hrs) or sending it to Apple (2 weeks?)...

What would you recomend?? Wait for update?

I would not recommend doing anything the common call centre recommends. It is not a solution to this problem. Wait for another couple of weeks for apple to admit their problem.

I have just tried using the SIM PIN workaround (change SIM PIN from default value, then disable SIM PIN), and bizarrely I have now been able to switch from WiFi to mobile broadband twice (by walking to the bottom of the garden)! This may just be a coincidence - I'm not sure that switching fails every time. However, I'd be interested to hear other people's experiences after changing and disabling the SIM PIN...

I'll post again if the problem recurs (probably very soon)!

David

I had already changed the sim password a while ago and tried disabling it completely today and it worked once, but that was probably because I had rebooted just before leaving the house. But I just switched off WLAN now and it wouldn't connect to 3G, so it doesn't work after all.

Selecting carrier manually apparently works. This setting is on "automatic" by default.If this is it, a stupid mistake is gonna cost Apple.

Nope sorry, i tried this for the past two days, it dosnt solve the problem. I had it manually set to tmobile uk and still had to reset the ipad to get 3g working after leaving home today.

The same here in Italy, 32gb 3G wifi & sim Vodafone.

Exactly the same issue since the first day I've bought.

To All on this thread.

Have spent many hours researching the Telco connection services. The problem resolves down to available privately assigned and publically assigned cellular network addressing. The networks generally, when working with public available addressing will typically lease a connection for a couple of hours and then release it back into the public pool. Your phone number tells your network who you are, but the IP tells the network where your required data needs to go. Due to the limits of available addressing, alot of IP addresses are now shared by the data providers in an attempt to overcome limitations of this oversubscribed IP addressing (IPv4 since a greater proportion of the internet falls back on to this standard).

When you are on wireless at home you have a DHCP address leased to your device by the Router. If you have a 3g signal as well, then you will also be leased the IP address connected with that. However, and this is where I think the problem lies, there are three different types of connection handshaking that occur. Mobile terminated, mobile initiated and one frequently used in GPS associations, where both client and host initiate and terminate in tandem.

What this means is that if you have a public leased IP from your data provider, which you have active whilst on a wireless network, because the IP is cached to your Data provider, who matches it to your subscriber number (your mobile telephone number) you will not notice it if the lease is terminated by your provider, since your adapter is handshaking with your provider via your mobile number.

Move out of range of your wireless and in this scenario, the previously cachedIP via your mobile number, because it is no longer available and a fresh connection has not been initiated by you, will now fail as a consequence.

Rebooting is one way to re-initiate the connection. However, if you get in the habit of either having wireless off, or your Data connection off in Settings, as you move out of or into the range of the other, you merely need to flick from off to on or on to off in each case. (See below though).

Whether Apple can improve the caching of IP's in relation to Data IP leasing, so it terminates a lease on the device as and when it is terminated by the Data Provider remains to be seen. In theory it should be possible.

However those who use home based PC's will know the problems of trying to initate a connection with their router when they have a browser window open - for some reason this blocks the connection attempt and the connection - if in automatic mode - and only initiates once the browser is closed. Similar problems occur if an email program is also open prior to connection - or - credentials are cached for one connection when you actually need the credentials from another source to then be active.

What annoys me more than anything else is the iPad display, which shows my Data network provider name when I am clearly on home wireless. In this scenario, if my IP address lease is terminated by my data provider, then i wont see the termination,because the IP credentials are cached to my device, via a <<live>> mobile number connection. Only switching off either the device or, wireles/data carrier setting in Settings will cause the device to seek to renew the connection lease and dial up for a new IP address. The problem is compounded by disconnect intervals that need to elapse for data to be refreshed at both the subscribers end (the device) and by the provider, via the network routing tables that serve the Masts (nodes).

If Apple can find a patch that only polls for a Data Carrier signal when wireless is unavailable or gets dropped, this would help - or at least a way of my device to sniff the cached address to see if it is still current. Using, the time service polling interval for instance to establish whether it is coming in on wireless or available through the Data Carrirer's connection might be one way of addressing this problem. The device could then automatically initiate a fresh handshake routine in the background to ensure I always have a current network connection via my data provider. Better still, my Data provider, in this scenario might be able to find a way to seamlessly transfer my terminated IP lease to a new IP.

A link for some of my study can be found at

ftp://ftp1.digi.com/support/documentation/appguide_connectcellular_ipconsiderati ons.pdf

For once it seems that this is NOT a problem we can lay squarely at Apple's door, though in fairness, and with regard to the technology that they are employing, perhaps Apple could work more closely with the Data Providers to ensure we have a better, consistent and a more seamless service. It costs us enough.

Regards. Ct

Change the pin of sim and change the sim It doesn't solve the problem.Hardware or software problem?

I thought iPad 3 comes with 4G, doesn't it? What provider are you using it?