Problem with mobile data in LTE/3G/2G network mode (Samsung Galaxy A5 2017)

[Anonymous]

Hi,

I have a new Samsung Galaxy A5 2017 with an O2 SIM (Pay as you go/Big Bundle, I used the same SIM already in my previous phone). I get good mobile data if I use the ‘3G/2G’ network mode. If I select the ‘LTE/3G/2G’ network mode, however, I get mobile data only very sporadically (especially after disconnection from Wifi, I do not have any mobile data). But there is definitely good 4G signal available at my place.

The APN settings seem to be correct. I’ve also tried to text ‘ACTIVE’ to 2020 but I did not receive anything in return.

Any ideas what to do to get proper LTE or 4G mobile data?

[Anonymous]

I have checked my ‘My O2’ account and I am definitely on a ‘£10 data Big Bundle’ (including ‘100 minutes, 100 texts and 1GB of 2G/3G/4G data in the UK for £10 a month’) and not on the Blackberry tariff. My only Bolt On if the ‘O2 Travel Opt Out’.

The odd thing is that I sometimes get 4G signal (so it generally works). However, after the phone disconnects from Wifi it does not get any mobile data signal anymore except if I change the network mode to ‘3G/2G’.

[MI5]

You have no way of knowing what tariff o2 have you on without calling them.

[Anonymous]

I now have talked to the O2 customer service and the tariff is definitely the ‘£10 data Big Bundle’.

I have asked them about my problem and they suggested that it may be caused by the SIM. They will send me a new SIM in the next few days. I will try it, however, I am not sure whether it can really be the SIM as the problem appeared when I have changed my phone (and my old phone worked well with the same SIM).

[MI5]

Data tariff is what we are talking about, not which bundle you are on.

[jonsie]

What bolt ons do you have showing in My O2? 

[Anonymous]

I am not sure what exactly you mean with ‘data tariff’, @MI5. According to both, O2 customer service and my ‘My O2’ account, I am on the ‘£10 data Big Bundle’ with a ‘100 minutes, 100 texts and 1GB of 2G/3G/4G data in the UK for £10 a month’ tariff. Are there further specifications within this tariff?

My only Bolt On if the ‘O2 Travel Opt Out’ according to my ‘My O2’ account.

[MI5]

The data tariff is what kind of data your phone receives from the network and is set on o2’s server.
If they don’t have the correct tariff for your type of phone you can lose 4g data.

[Anonymous]

I have received my new SIM from O2 but unfortunately the problem is still present. I have tested the (new) SIM in my old phone (a Samsung Galaxy S5 mini) and switching between 3G, 4G, and Wifi worked perfectly.

I also went to the O2 shop and they told me that it is not a problem of O2 but most likely of my phone. I think they may be right as 4G is generally working. I also found out a ‘trick’ to make it 4G connect: Under the radiator in my flat there is only 3G signal. If I put the phone there in LTE/3G/2G network mode and deactivate Wifi it connects to 3G. Once connected to 3G, it automatically switches to 4G if I bring it to another place. If I switch off Wifi when 4G signal is available, however, it does not connect to mobile data.

As I have warrantee on my new device, I will try to get a replacement. I hope this is not a general bug in the Samsung A5 2017.

[MI5]

I think we've exhausted every other possibility so it must be a phone fault now.

[Anonymous · Accepted solution]

I have now received my replacement phone and switching between 3G, 4G, and Wifi works without any problems (with the same O2 SIM). So there was apparently something faulty with the other device. Thanks again for your advice.