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Richard, Engineer
Category: Electronics
Satisfied Customers: 44593
Experience:  Electronics Engineer
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I have a Samsung J7 with Dual Sim that I bought in the US.

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I have a Samsung J7 with Dual Sim that I bought in the US. Have used back home in UK as well as Japan with no issue. I think that since I had an upgrade its caused the SIM manager to switch between SIM's sadly even if only one SIM fitted, which means signal keeps dropping, and kills battery. Its running Android 5.1.1

Hi there and welcome

You mean it just keeps hoping between the sim ports Steve on its own?

Customer: replied 1 year ago.
thats correct, at least thats what I think is happenning. Im not on the device, and I currently dont have a sim in it, how do you connect to it??

Ok, remove the battery and wait 5 minutes, put the battery back in, turn it on and tell me how it then performs please

Customer: replied 1 year ago.
Intermittantly displays 'No Sim Card No Service'. ok taken battery out. ive been using my old phone for 2-3 days so its been off for a while

ok, let me know the results please.

Customer: replied 1 year ago.
the same. though i havent seen it try to switch to other sim. it is now saying no service most of time. works fine in my samsung note 2. i hate intermittant problems. im prepared to go online if you are confident you can sort

Can you go to Settings, Applications Manager.

Swipe to the list all and locate Google Services Framework

Press it and press clear data.

Once done, restart the phone and tell me if it now connects please.

Customer: replied 1 year ago.
sorry nothing saying google service framework under apps manager. i did do a factory data reset earlier.

its under the list ALL but if you did a factory reset then that is the next step anyway.

This means it is not software related.

If you put the sim card in the second port, does that get connected?

Customer: replied 1 year ago.
tried that, the same. Sadly I dont have a second sim to try both. I was kinda hoping this was a known issue,

It is but there are three causes for it, either the firmware or the mainboard as you ruled out the sim card as the issue as it works in another phone. There the only reasons for this.

I was hoping at least the 2nd port was working, but if this is not the case it means the mainboard has been damaged and its not able to talk to the network. It will likely be the antenna on it

I am really sorry about this and you are going to have to return the phone to have this replaced. It is a known problem, so it will be covered by the warranty if this has not expired, and the replacement will be done at no cost to you. If you have problems, or would like any additional information or assistance, please do not hesitate to let me know. And if you can take a second to rate my service by clicking one of the stars at the top of the page, then submit, that would be greatly appreciated. Thank you
Customer: replied 1 year ago.
Okay thanks

Your welcome Steve, if you need anything else, please let me know

And please remember the service rating via one of the stars at the top then submit

Thank you

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