How to Switch Your Nexus 5 or 6 From CDMA to GSM Without a Factory Reset

Posted: February 14, 2015

Nexus 5

Recently I switched my Nexus 5 from Ting’s CDMA service to their new GSM service. Unfortunately it is not quite as easy as plugging in the GSM SIM card - a few settings need to be changed for everything to work properly. Most cell phone providers and even the forums I have read suggest doing a factory reset and wiping the entire device just to switch between CDMA and GSM. Although I am sure that works, it is really overkill and not required.

There are two main ways to switch back and forth. This first method is best for those who may want to switch from CDMA to GSM but want their current CDMA settings to remain intact. If you use this option, going from GSM back to CDMA is as simple as inserting the CDMA SIM card - the Nexus 5 or 6 will recognize it is back on CDMA and switch immediately. This assumes that you have two active numbers: a CDMA line and GSM line. If you want to switch from CDMA to GSM permanently, the second options is best as it resets all the carrier settings.

Follow these direction to switch from a CDMA number to a GSM number and SIM card.

  1. Go to Settings → More → Cellular networks → and change Preferred network type to “Global."
  2. Take out your CDMA SIM card and replace it with an active GSM SIM.
  3. A new menu should appear called Access Point Names within the Cellular networks menu.
  4. Select Access Point Names and select or enter the appropriate APN information.
  5. Now select the Network Operators menu and tap "Choose Automatically" which will register you on the GSM network.

1 Settings 2 More... 3 Cellular Settings CDMA 4 CDMA Global 5 Cellular Settings GSM 6 APNs 7 Choose Automatically

This is the other way that works... you don't need to do both. This is probably the easiest way, but erases your CDMA network settings. It is best for those switching to GSM permanently.

  1. Have your SIM eject tool ready.
  2. Go to the dialer and dial *#*#72786#*#* (note you must have the CDMA SIM in and have some signal for this command to work) and immediately remove the CDMA SIM. This will erase the CDMA carrier settings.
  3. Now put the GSM SIM in while the phone is restarting. It should automatically switch to GSM and pick up the GSM service but you will see a exclamation point next to the signal strength icon indicating a problem. That is because you haven't set up the APN yet.
  4. Go to Settings → More → Cellular networks → and you should now see Access Point Names.
  5. Select one of the default APNs or create your own.
  6. Restart the phone and everything should work.

Note that both methods will work even if your device is still registered to the CDMA carrier. However, the first method is the only one that keeps your CDMA settings intact so you can switch between CDMA and GSM quickly by swapping out SIM cards and restarting. For example, my Nexus 5 is active on Ting’s CDMA network as well as the new GSM network and is relatively easy to switch back and forth now. Note that both CDMA and GSM service cannot be active at the same time.


Ryan Melena said...

Does Ting require you to have 2 lines (one GSM and one CDMA) or do both sim cards fall under a single line?

Cam Medlin said...

If you want both CDMA and GSM service you will need 2 separate lines and SIM cards. One Ting SIM card can't switch between networks at this time (unlike Google's Project Fi).

This article was primarily for people who had CDMA service on Ting and wanted to try out the new GSM service on their nexus 5/6.

Brad Robbins said...

Thanks for this. I was using two separate phones on Ting for CDMA and GSM coverage when travelling (and it gave me double the battery!). I just got the Nexus 6 and will be paring down to one phone and an ancient Optimus G as a backup for long trips.

Christopher DiSanto said...

I'm going to the UK for 15 days, and with Ting's international rates, the fee's add up fast. I found that T-Mobile's Simple Choice Plan is cheaper and one month no commitment. However, my Nexus 5 is CDMA on Ting and T-mobile says their sim is not compatible. If I buy the T-Mobile sim can I change my phone over to GSM for the time that I'm gone, then just plug my CDMA Ting Sim in once I get back stateside?

Cam Medlin said...

Yes, you can do that. Whoever told you T-mobile doesn't have a compatible SIM is incorrect. You can get a free SIM that has a micro adapter from T-Mobile and it will work just fine. When you get back just swap back the CDMA SIM using the instructions in this guide.

yuan said...

Hi I am a little confused. I used my nexus 6 on sprint first then I switch to ATT. I didn't have to do any settings at all. All I did was just swap sim card and everything works (including LTE, and even the APN is pushed to the phone automatically when pop in an ATT sim). So my question is what are the methods mentioning in the articles for? Thanks.

Alaa said...

Hi, In my case I was using a CDMA sim card in US with ting on my Nexus 5 and I traveled to Egypt for 1 week where I switched to use my old GSM sim card, I didn't configure any settings. I inserted the GSM sim card and it works fine (just moved to Global option in data instead of LTE).
However, when I returned back to US and inserted CDMA sim card of ting, it is no longer working, I cannot make calls, I can send/receive sms or receive calls sometimes but I cannot make calls! When I contacted ting, they tried many many solutions and failed. The last thing they said is that the CDMA part is problematic now due to using the GSM sim! and they will ship me a new GSM sim card and I will not be able to use CDMA sim cards anymore!

Cam Medlin said...

Unless your phone is somehow broken you should be able to get CDMA to work again. Using GSM doesn't change anything about the phone itself - it is still compatible with Ting's CDMA service. Try a factory reset. If that doesn't work, flash the factory image.

Alaa said...

@Cam Medlin: I already tried factory reset and doesn't work.
could you elaborate what do you mean by flash the factory image?

Cam Medlin said...

Sure. You download the appropriate (the last one in the Nexus 5 list) factory image at the link I provided, then flash the image from your computer to your phone. It is not very difficult... there are multiple guides and videos online. We even have a how-to guide here. Our instructions were written for the Android L developer preview a while ago, but the instruction are the same, just the file names will be different.

Megha Sharan said...

Hey Cam,

Why is Ting name shown 3 times in the network selection menu? AFAIK it's supposed to show operators present in that area like AT&T, T-Mobile. Why Ting 3 times?