Why wont a CDMA Sprint S8+ translate to T-Mobile, but says ok for Verizon GSM?

[Android Central Question]

I work for a retailer, had S Series Samsung fanatics in the store that I got really nice Moto E5 Plus for the sales tax only switcher promo as a back up to the S8+ phones from Sprint. They wanted the S series back on account right away - so they, with my assistance, WE -- called Sprint to pay off the balance on the phones. Process done over a few days to unlock. Come back in - device change - nothing.... No signal.... Nothing.....
I call Sprint, talk to supervisor as he is snickering through clenched teeth tells me phones say okay for US Cellular and Verizon but not T-Mobile. Verizon is GSM why wouldn't it translate to T-Mobile? Does Sprint have to do Network and not just Carrier unlock to make it work - and how criminal is that not to have disclosed that to the customers after paying $600+ for the remaining balance? I swear I have done CDMA phones as BYOD on GSM network that worked right away. Aside from wrong IMEI and SIM numbers what is the answer? I saw them pay over phone with card for unlock.

 

[mustang7757]

Hi, welcome to AC forums, me or other members would be happy to assist you but if we need to ask additional questions you'll need to register as a member to respond . I'll provide a link to register so you can reply and communicate with us .https://forums.androidcentral.com/showthread.php?t=409154

I work for a retailer, had S Series Samsung fanatics in the store that I got really nice Moto E5 Plus for the sales tax only switcher promo as a back up to the S8+ phones from Sprint. They wanted the S series back on account right away - so they, with my assistance, WE -- called Sprint to pay off the balance on the phones. Process done over a few days to unlock. Come back in - device change - nothing.... No signal.... Nothing.....
I call Sprint, talk to supervisor as he is snickering through clenched teeth tells me phones say okay for US Cellular and Verizon but not T-Mobile. Verizon is GSM why wouldn't it translate to T-Mobile? Does Sprint have to do Network and not just Carrier unlock to make it work - and how criminal is that not to have disclosed that to the customers after paying $600+ for the remaining balance? I swear I have done CDMA phones as BYOD on GSM network that worked right away. Aside from wrong IMEI and SIM numbers what is the answer? I saw them pay over phone with card for unlock.

 

[Rukbat]

Sprmt, US Cellular and Verizon are CDMA carriers, TMobile (And AT&T) are GSM carriers. Totally different technologies. The S8 comes in 2 variants - CDMA and GSM. (Then the GSM variant comes in a few sub-variants.) So for TMobile, they need the G950T. Sprint uses the G950P; Verizon uses the G950V and US Cellular uses the G950R4. The E5 is a GSM phone. So they can use their S8+ on Sprint, or they can get a G950T, the G950P won't work. (Some of the newer flagships have both radios, so one phone works on both - the S8+ isn't one of them.) If you don't carry Sprint, you've lost a customer, unless you can convince them to buy a G950T.

A CDMA phone doesn't hear a GSM signal, all it hears is noise. (And vice-versa - a GSM phone hears only noise from a CDMA signal.)

 

[Ry]

I work for a retailer, had S Series Samsung fanatics in the store that I got really nice Moto E5 Plus for the sales tax only switcher promo as a back up to the S8+ phones from Sprint. They wanted the S series back on account right away - so they, with my assistance, WE -- called Sprint to pay off the balance on the phones. Process done over a few days to unlock. Come back in - device change - nothing.... No signal.... Nothing.....
I call Sprint, talk to supervisor as he is snickering through clenched teeth tells me phones say okay for US Cellular and Verizon but not T-Mobile. Verizon is GSM why wouldn't it translate to T-Mobile? Does Sprint have to do Network and not just Carrier unlock to make it work - and how criminal is that not to have disclosed that to the customers after paying $600+ for the remaining balance? I swear I have done CDMA phones as BYOD on GSM network that worked right away. Aside from wrong IMEI and SIM numbers what is the answer? I saw them pay over phone with card for unlock.

Did Sprint unlock it or did they pay a third party to unlock it?

 

[Ry]

Sprmt, US Cellular and Verizon are CDMA carriers, TMobile (And AT&T) are GSM carriers. Totally different technologies. The S8 comes in 2 variants - CDMA and GSM. (Then the GSM variant comes in a few sub-variants.) So for TMobile, they need the G950T. Sprint uses the G950P; Verizon uses the G950V and US Cellular uses the G950R4. The E5 is a GSM phone. So they can use their S8+ on Sprint, or they can get a G950T, the G950P won't work. (Some of the newer flagships have both radios, so one phone works on both - the S8+ isn't one of them.) If you don't carry Sprint, you've lost a customer, unless you can convince them to buy a G950T.

A CDMA phone doesn't hear a GSM signal, all it hears is noise. (And vice-versa - a GSM phone hears only noise from a CDMA signal.)

This is probably incorrect. If SIM-unlocked, it should work.

 

[Ry]

I work for a retailer, had S Series Samsung fanatics in the store that I got really nice Moto E5 Plus for the sales tax only switcher promo as a back up to the S8+ phones from Sprint. They wanted the S series back on account right away - so they, with my assistance, WE -- called Sprint to pay off the balance on the phones. Process done over a few days to unlock. Come back in - device change - nothing.... No signal.... Nothing.....
I call Sprint, talk to supervisor as he is snickering through clenched teeth tells me phones say okay for US Cellular and Verizon but not T-Mobile. Verizon is GSM why wouldn't it translate to T-Mobile? Does Sprint have to do Network and not just Carrier unlock to make it work - and how criminal is that not to have disclosed that to the customers after paying $600+ for the remaining balance? I swear I have done CDMA phones as BYOD on GSM network that worked right away. Aside from wrong IMEI and SIM numbers what is the answer? I saw them pay over phone with card for unlock.

Can you connect it to WiFi with the T-Mobile SIM installed?

 

[B. Diddy]

It looks like the Sprint S8+ does in fact have a GSM radio, so the main question here is if it's locked to Sprint.

sprint.com/en/legal/unlocking-your-sprint-device.html

 

[Ry]

Skimming through search results, it looks like what's supposed to happen is that settings for T-Mobile are supposed to be automatically downloaded when the T-Mobile SIM is installed.

 

[Rukbat]

And if it's SIM-locked, there would be a popup asking for the unlock code.