Temporarily move SIM from 3GS to 3G?

[Undecided]

I use a 3GS but I also have an unlocked 3G and want to take that with me traveling internationally, so if it's lost or stolen, no big deal - I come home to my 3GS (and I'd rather not unlock my 3GS).

Can I just take the SIM out of the 3GS and move it to the 3G, and it should work both here and abroad?

I just tried it, and it said "Searching..." where it normally indicates signal strength, and eventually says, "No service."

Should I be able to just pop in the SIM and go? Or do I have to "activate" in some way? (I don't want to risk relocking it.)

 

[atlanticza]

Wouldn't it be simpler just to buy a pay-as-you-go sim card in the country you're travelling to? (On another note, I too had that problem of No Service. Turns out that the sim card was faulty.)

 

[Undecided]

Oh, yes, that's what I plan to do. But I wanted to move my SIM card here/now to (a) confirm that it as actually unlocked (and doesn't need iTunes to get it to work, once I arrive) and (b) so I can use my SIM in the 3G to/from the airport, etc. Mainly (b) - I popped an unactivated T-Mobile SIM into it, and while it said no service, it didn't ask for some sort of PIN or whatever, which supposedly is good enough to indicate that it is, in fact, unlocked.

I definitely don't want to assume it's all good, arrive, buy a sim, pop it in it, and have it still say "no service." Major bummer.

 

[awadeee]

If the phone was 'hactivated' you may run into an issue with service.

Try restoring the 3G with iTunes and activating it officially with your SIM. If you're on 6.15.00 baseband you'll have to use a custom IPSW.