[SOLVED] I installed my old phone's motherboard into a new, identical phone. The new SIM card is activated, but does not function on the old mobo?

Kawaii Penguin

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May 21, 2015
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Hi, guys. I'm having trouble lately getting my new phone to work.

Brand: ZTE Zmax Pro Z981
OS: Android 6.01 - Marshmallow
Carrier: MetroPCS

The gist:
The SIM card does not work. I've tried setting up the network by going into mobile network settings & manually choosing the network operator as MetroPCS (my current carrier), but it rejects the SIM card, giving the error: "Your SIM card doesn't allow a connection to this network."
I am currently unable to contact their call centers due to this pandemic going on - they closed down their centers entirely. I want to see if there's a way to fix this issue without having to file a request to them.

The details:
This is a weird situation, for sure. Partly why I decided to post it in the Android & Chrome OS forum as well - because I'm not sure if this is an issue in the software or just the SIM card / provider.

I salvaged the board from my old phone (which has a badly damaged screen) and decided to stick it into a replacement phone (same brand & all). I wanted to use my old board because I had a lot of stuff in the storage and I liked the current settings I was using.. also, the new motherboard was extremely sluggish and seems to have had some damage to the GPU. This may have been my fault. I was taking every precautions necessary, though, so I feel like it could've been the manufacturer. I'm not too sure.

Anyways.
The installation went okay, my main concern now relies with the actual SIM card. For some reason, it's not activating like it should.

I was able to get it to work on the new motherboard, but the new motherboard is extremely sluggish, as mentioned prior. The operating system was constantly crashing.


Tonight, I'm going to attempt to activate it on the new motherboard, as the cellular connection had worked previously. Then I'm going to swap out the boards and hope the motherboard doesn't have some form of unique identifier.
I'll get back to this post if the above works or not, but please lend me suggestions if you have any in the mean time.
 
Solution
Currently on the new motherboard. Things are sluggish but, eh.
I managed to automatically connect to a cellular network with the last mentioned method. It still did not give me a proper cellular connection, though.
I managed to get some statistics out through a diagnostics app. Even though my provider was MetroPCS, I'm somehow automatically routed to Verizon. The data connection is going in and out, mostly out. What in the world is going on? e_e
https://prnt.sc/roop63

Contact you carrier, swapping system boards is the same as getting a new phone. They will need to activate that new phone on their service with your card.

Kawaii Penguin

Honorable
May 21, 2015
132
1
10,715
The issue at hand:

<<Link removed by moderator>>

Brand: ZTE Zmax Pro Z981
OS: Android 6.01 - Marshmallow
Carrier: MetroPCS

The question for this subforum:
I want to know if a motherboard can store some form of unique identifier to determine whether or not the SIM card can function on it.
My previous motherboard that I'm currently trying to use on my replacement phone is being denied access to the SIM card. It's the exact same brand of phone and everything - so what gives?
 

Kawaii Penguin

Honorable
May 21, 2015
132
1
10,715
Currently on the new motherboard. Things are sluggish but, eh.
I managed to automatically connect to a cellular network with the last mentioned method. It still did not give me a proper cellular connection, though.
I managed to get some statistics out through a diagnostics app. Even though my provider was MetroPCS, I'm somehow automatically routed to Verizon. The data connection is going in and out, mostly out. What in the world is going on? e_e
https://prnt.sc/roop63
 
Currently on the new motherboard. Things are sluggish but, eh.
I managed to automatically connect to a cellular network with the last mentioned method. It still did not give me a proper cellular connection, though.
I managed to get some statistics out through a diagnostics app. Even though my provider was MetroPCS, I'm somehow automatically routed to Verizon. The data connection is going in and out, mostly out. What in the world is going on? e_e
https://prnt.sc/roop63

Contact you carrier, swapping system boards is the same as getting a new phone. They will need to activate that new phone on their service with your card.
 
Solution
Currently on the new motherboard. Things are sluggish but, eh.
I managed to automatically connect to a cellular network with the last mentioned method. It still did not give me a proper cellular connection, though.
I managed to get some statistics out through a diagnostics app. Even though my provider was MetroPCS, I'm somehow automatically routed to Verizon. The data connection is going in and out, mostly out. What in the world is going on? e_e
https://prnt.sc/roop63

Contact you carrier, swapping system boards is the same as getting a new phone. They will need to activate that new phone on their service with your card.