[tle708]

Hi everyone,
I bought the phone on eBay, unlocked (##7820# checked). It worked with T-mobile just fine at first then suddenly stop receiving T-mobile signal after several updates (it isn't because of the update though I tried to downgrade it to Denim and it doesn't work still). I called T-mobile and they couldn't help. I am not AT&T customer so I have no right to call them. Does anyone have any idea?
Thanks guys

[heywhitmarsh]

Go to settings/cellularSIM/SIM settings/
then hit the Network selection box and select search for networks
In most places you should see T-Mobile and AT&T come up, while Verizon will show up occasionally. If T-Mobile shows up in the list, try selecting it and see if that helps. If it doesn't show up in the list but other networks do show up, the problem is less likely to be from your phone. If no networks show up, then the problem might be a hardware issue with your phone.

[ScrubbyXD]

dial ##3282#
enable all bands

There is a field test mode step by step somewhere around here.

[RumoredNow]

There is a field test mode step by step somewhere around here.

http://forums.windowscentral.com/nok...-band-4-a.html

But that doesn't sound like the problem:

It worked with T-mobile just fine at first then suddenly stop receiving T-mobile signal after several updates (it isn't because of the update though I tried to downgrade it to Denim and it doesn't work still).

The how to enables one T-Mo 3G band. OP is getting no signal.

It sounds like the downgrades and resets have eliminated software. It may be a bad antenna or a bad connector.

[ScrubbyXD]

My point in advising the action was to ensure that the OS was indeed using all available bands. This was in case (as you say) there was data corruption. And that data corruption turned off whatever band(s) his area uses. After that quick fix is exhausted it is time for a wipe most likely.

All the while here the OP needs to be watching for any oddities in his navigation button LEDs or call microphone. Usually (but not always) you see some intermittent issues in all functions of that board when it's going out.