Captivate not registering on network/holding signal

[Azure1203]

Yes, I have read every other thread I could find.

Anyways, I bought a Samsung Captivate on Kijijii. I did test it before I bought it, and it picked up 5 bars, and more importantly, held the 5 bars.

Took it home, and ordered the unlock code, which took a few days to get through. In the meantime I upgraded the phone from 2.2 to 2.3.3. Everything seemed to be fine. Got the unlock code, put in my SIM card, put in the unlock code....everything worked perfectly. It didn't pick up a signal though at first, which is a problem with my carrier(I think). They make you go in and manually search and then register. Which I did. Well, for the longest time it wouldn't find the carrier. I have pretty crappy service, so I went outside, still nothing.....went to work and stood under a cell repeater which gives 5 strong bars to any other phone, and my Captivate would show my carrier, I would register, and it would get 1 bar, and then within 10 seconds, it would lose signal again. All while I was standing right beside the cell repeater.

Not only that, but for some reason it would turn on flight mode, and then when I would try to disable it, it would sit there for about 20 min doing nothing.

I went back to 2.2.....still did the same thing. Went to 2.3.3 again, still the same problem. Tried 3 different modems for my specific model phone, 1 of them would find the network instantly, register within 10 seconds, and then drop signal again and go into enabling flight mode, and being a general pain in the ass to turn off. I would actually have to reboot the phone to be able to search for networks again.

The phone came from Rogers, so I put in my brothers Rogers SIM card, and it instantly found the network, registered and gave me 2 bars without me having to do anything. Except then it began dropping signal, getting signal back...dropping it, getting it back. It is winter here right now, and we do have spotty service, but I have Samsung Fascinate that holds at least 1 bar consistently. Not sure if the antenna strength is better. From what I understand they are more or less the same.

I swapped out my SIM card into a different unlocked phone and got service instantly, and then put another different SIM card into the Captivate, and it had the same problem.

I'm pretty much out of options. I'll try tomorrow to see if I can hold a Rogers signal better, which it hopefully can because I'm thinking of selling it.

But I'm inclined to believe that it might be a software problem. Problem is I have no idea what to do in order to fix it.

Any help would be greatly appreciated. Thanks!

 

[Azure1203]

Played around with it a bit more. On 2.3.3 with the KH3 modem installed, it will find the network, then try to connect for 10 min, where it will then say 'unable to connect, please try later.'

Then after clicking again, it will say 'unable to connect, select automatic registration' and then sit there for another 5 min. When it finally comes back, I will click on 'select automatically' and it will say after a couple min, 'registered on network', but won't get signal.

All of this I do with 5 bars service. Or in an area with 5 bars service.

Also, the flight mode constantly comes on, and disables 'mobile networks'....so I can't access it. And its a bit weird that it would do that, since any other android phone that I've had, when I lost service, it would constantly try to connect, not go into flight mode and refuse to come out.

Would it help to install a custom ROM on it? I'm going to try going back to 2.2 and test some more stuff. Problem is the small amount of time I spent with 2.2 last night, the phone would crash everytime I tried searching for networks.

 

[Azure1203]

After playing around with it even more, I'm convinced that it says 'error while searching for networks' because the phone constantly jumps back into flight mode.

Even when it does get a signal and registers, the phone jumps back into flight mode within a couple seconds, and bang the signal is gone.

 

[holeindalip]

Are you flashing with the sim card in the phone? Or if you are flashing through cwm are you leaving the usb cable plugged in?

Sent from my SGH-I897 using XDA App

 

[Azure1203]

Are you flashing with the sim card in the phone? Or if you are flashing through cwm are you leaving the usb cable plugged in?

Sent from my SGH-I897 using XDA App

I flashed with Odin, WITH the SIM card in the phone. I never bothered to take it out. Would it make a difference?

I actually just flashed back to 2.2 with the SIM card in the phone. It found the network, registered on the network, but then dropped signal and activated flight mode again.

Odin flash goes like this. Put phone into download mode, plug phone into USB, open Odin, put 2.2 file into 'phone' section, make sure re-partition isn't checked, click start, and it does everything it should do. Phone restarts running 2.2.

 

[b-eock]

No open ODIN FIRST!!! And then plug in phone... know your stuff before you give false info.

Sent from my SAMSUNG-SGH-I897 using xda premium

 

[Azure1203]

After flashing back to 2.3.3 without the SIM card in the phone, I still get the same problem. But the phone doesn't seem to constantly be going back into flight mode.

Does the modem file change if you go back to 2.2 and back up to 2.3.3? I might have flashed the wrong modem or something.

 

[Azure1203]

No open ODIN FIRST!!! And then plug in phone... know your stuff before you give false info.

Sent from my SAMSUNG-SGH-I897 using xda premium

I'm not quite sure what you mean. I've done it both ways, and each time the flash has been successful.

 

[Azure1203]

I should mention that baseband version on my status menu says 'I896UXKH2.'

And I'm running 2.3.3.

So I'm not sure if the modem changes when you go back to 2.2. I forgot to check that.

 

[holeindalip]

I thought you were suppose to put it in the pda slot not the phone??

Sent from my SAMSUNG-SGH-I897 using XDA App

 

[Azure1203]

I thought you were suppose to put it in the pda slot not the phone??

Sent from my SAMSUNG-SGH-I897 using XDA App

I did actually put it into the PDA slot. Sorry.

Anyways, rooted and installed CM7, installed the KC1 radio, which SHOULD work in Canada on the 850mhz band, and when I search for networks, the only network it finds is Can Rogers Wireless Inc. Up till now it found MTS as well, which is the network I want to use.

I have an MTS(working SIM card) inside the phone. Just bizarre. Could the unlock code not have worked correctly?

 

[Azure1203]

Just completely bizarre. I couldn't get any modem to even recognize and find my network of choice, MTS.

So I went back to exactly how the found was when I bought it. Stock 2.2. Going to find out if even a Rogers SIM card will work in it.

 

[bindaasathar]

There could be two possible things:
1. Unlock code would had messed up.
2. Corrupt IMEI number! Check IMEI number on the box of your phone or below battery and compare with that of the phone (*#06# or settings)...

 

[holeindalip]

There could be two possible things:
1. Unlock code would had messed up.
2. Corrupt IMEI number! Check IMEI number on the box of your phone or below battery and compare with that of the phone (*#06# or settings)...

+1 you beat me to it!



Sent from my SAMSUNG-SGH-I897 using XDA App

 

[Azure1203]

There could be two possible things:
1. Unlock code would had messed up.
2. Corrupt IMEI number! Check IMEI number on the box of your phone or below battery and compare with that of the phone (*#06# or settings)...

The IMEI number on the status menu on the phone is identical to the phone under the battery.

So that leaves the unlock code. The guy who gave it to me, cellunlocker.net gave me instructions for locking it to a specific carrier. I tried that with MTS, and it doesn't work. Basically you punch in a code in the dialer, put in the MCC/MNC code, put in the network lock code, and lock it for that carrier. It said it worked successfully, so I have no idea what else went wrong.

The instructions I mentioned above he gave me after I told him the original method didn't work. That method being putting in non-accepted SIM card, and the box pops up asking for network unlock code. I punched the code in he gave me, and it said unlock successful.

Anything else I should do?

 

[tennyleaz]

I have the similar problem on any 2.1~2.3 stock firmware which I have tried.
I'm using Tmobile now, and the IMEI is correct.
But I only receive 1 bar or no bar signals.

 

[Azure1203]

I have the similar problem on any 2.1~2.3 stock firmware which I have tried.
I'm using Tmobile now, and the IMEI is correct.
But I only receive 1 bar or no bar signals.

So you unlocked your phone as well? Perhaps the bands are wrong? I know T-mobile uses a different band than other US providers.

In my case, the Captivate uses the 850/1900 bands, which is what Rogers and MTS use.

MTS being the carrier I want to use it on.

 

[codwif]

The IMEI number on the status menu on the phone is identical to the phone under the battery.

So that leaves the unlock code. The guy who gave it to me, cellunlocker.net gave me instructions for locking it to a specific carrier. I tried that with MTS, and it doesn't work. Basically you punch in a code in the dialer, put in the MCC/MNC code, put in the network lock code, and lock it for that carrier. It said it worked successfully, so I have no idea what else went wrong.

The instructions I mentioned above he gave me after I told him the original method didn't work. That method being putting in non-accepted SIM card, and the box pops up asking for network unlock code. I punched the code in he gave me, and it said unlock successful.

Anything else I should do?

I ordered my unlock code from cellunlock.net and it didn't take. I used the Galaxy S Unlock app and it worked fine. When you enter *#7465625# it does show the network lock as off right?

 

[Azure1203]

I ordered my unlock code from cellunlock.net and it didn't take. I used the Galaxy S Unlock app and it worked fine. When you enter *#7465625# it does show the network lock as off right?

Didn't take as in it said it cannot unlock? Because when I put in the code from cellunlock it said unlock successful.

But I didn't know you could check with that code. I'll do that later. Thanks.

 

[Azure1203]

So apparently I had locked the phone to MTS. Put in a Fido SIM card to try something different, and it said enter network unlock code. Entered the unlock code I got, and it said unlock successful.

Now when I type in *#7465625# it says 'off' under all the headings, just like my Fascinate says.

It still holds signal, loses signal though with Fido. I have no idea if that is a problem or what is going on. It'll get 2 bars, or about -99dbm, 5asu, and then suddenly drop it. Get it back again....drop it after 10 seconds.

Apparently flight mode is going on, going off, going on, going off....which is apparently why it loses signal, and gets it back again.