Fairphone using a lot of power with second sim installed

For a year now I have been using my Fairphone 3 with a UK SIM (Tesco) and a Belgian SIM (Mobile Vikings) installed. I haven’t had any trouble with /e/ or the phone, it’s a great combination.

Soon I’ll be moving to Spain so I decided to swap out the Belgian SIM for a Spanish one (Orange) which I bought on eBay. The seller activated it with my ID and it works. But I started noticing severe battery drain after installing it, and the phone is warmer than usual.

To give you an idea, with the UK/BE SIMs installed, the battery lasted two full days, even with the phone configured at maximum performance. But with the UK/ES SIMs, I could barely get through the day without having to plug it in.

At first, I thought it may have had something to do with the Spanish SIM constantly looking for networks. I fixed it on one network with a good connection, but that didn’t change a thing. Yesterday I took it out and everything is normal again.

What can be the cause of this? Is there something wrong with the SIM? Do I need to check the configuration?

Did you try, having only the ES SIM installed ?

As I understand, you’re not in Spain right now : maybe it’ll work better in it’s home country ?
Also, you may be facing a corrupted (intentionally or not …) SIM, hard to tell …

You can check Orange ES APN settings against Orange Spain APN Settings - 4G 5G APN Settings


No, haven’t tried the ES SIM alone because I need to be able to receive calls on my UK number. But Sunday is a good day to test that out. :slight_smile:

You may be right about being abroad, it may work better once I’m in Spain. But I never had such issues with the BE SIM, and that one has been inside my phone for the past year, together with the UK SIM.

I’ve checked the APN before, everything is configured as it should be. I’m going to evaluate today with the ES SIM alone, but I can already feel the phone is warmer than usual, so I don’t have high hopes.

As a matter of precaution, I’ll ask for a refund/return.
The SIM card may contain a malware, getting your phone hot (CPU usage ?).

The OS doesn’t report any apps consuming an unusual amount of CPU power. I’ve checked for malware, but nothing could be found. The SIM in itself is too small to contain malware, I think, other than a stager. And the package came in unopened, undamaged; it doesn’t look tampered with unless they can flash a sim card without making physical contact.

I did read an article about the Spanish government tracking SIM cards from the three largest providers. Something I’m not surprised about, it’s really hard to trust them. Also not sure if that would have any impact on battery life.

But there is improvement in the situation. Yesterday I switched the Spanish card to slot 1 and the UK card to slot 2, and now it seems to be fine. I’ve fully charged the phone yesterday afternoon, and it’s now at 53%, which is about what I would expect. The phone also doesn’t run hot anymore. Fingers crossed! :slight_smile:

That’s good news :slight_smile:

Maybe something related to data, VoIP, call routing … Hard to tell !
Hopefully you can continue to use it in this way :slight_smile:

For information, a modern SIM card is not to small to contain some malware…

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For information, a modern SIM card is not to small to contain some malware…

That’s good to know! I thought they intentionally kept it small to avoid such security vulnerabilities.

Anyway, thanks for your help here!

I have the FP3+ (Android 10, /e/OS v. 0.17) with two SIMs since I bought it in May. At first, everything was going fine, until end of June/start of July that the CPU (and not the battery) started getting hot after using it to chat in Telegram and having 2 apps running at the same time. That way, the battery started draining faster. I don’t really know if the problem are the two SIMs (btw, both Spanish SIMs) or if it has something to do with the last /e/OS update. Or maybe both of them…

I haven’t had it after switching slots, until yesterday. Not sure what happened but the battery started draining really fast. It went from fully charged in the early afternoon to 25% around 10 PM and when I woke up the next day it was dead.

Now it’s ok again, really weird. I’m going to put the Spanish SIM in another phone and see what happens.

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Just a weird idea : can you try to force a SIM to use LTE/4G (the one with active data), and the other GRPS/2G ?

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Done! I’ve inserted the UK SIM in slot 1 and the ES SIM in slot 2. That’s the combination where it went wrong. The UK SIM is now on 4G and the ES SIM on 2G for about 14 hours, and so far so good. No overheating and battery levels are normal. I recharged it to 100% yesterday morning and this morning there is 68% left, so that’s really good.

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Nice to read that :slight_smile:

So we may have some conflicting issue when both SIM use LTE (and data ?).
Hard to say if it’s a software or hardware issue, maybe FP forums would be of help with this …

Meanwhile, if you want to improve the diagnosis you may try some other combinations, for example both LTE but everything (VoLTE, data, …) disabled on one SIM.

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Yeah, I’m happy to experiment some more. :slight_smile:

I’ve now enabled 4G on both and disabled everything data-related on the ES SIM. Let’s see how that goes.

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Good news again. This morning the battery was still 65% after fully charging it yesterday morning. So 4G on both SIMs and disabling data on one works as well.

To be honest, I don’t see the point of having two 4G data connections enabled all the time. I’d rather choose one manually because I’ll always be roaming with one of the two.

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Good news indeed ! :slight_smile:

I agree with you : data on both SIM is useless, except for specific use.
Unfortunately, /e/ (or LineageOS) may keep them active on both SIM in some cases.
Fortunately, this is an easy fix :slight_smile:

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