[Workaround and Cause] : Nokia 7 plus Restarts on charging

gowtham4us

Issue analysis: https://community.phones.nokia.com/discussion/comment/57866/#Comment_57866  .


Workaround for now, to avoid restarting:

Use normal charging adapter ( charging speed< 1000 mA/sec ) [ use of poor quality adapter is not recommended ]

[OR]

Use your mobile while charging ( If the mobile screen is ON while charging, Turbo charge will not happen. Thus, restart will not happen ).


P.s: I m using "AccuBattery" app to find charging speed in mA/sec .


Please contact Nokia support and share the above link (as I did). As the dev team is notified, chances are more to get a fix soon.

Hoping to get a fix from Nokia soon.

@HMD_Laura FYI ( as I have found some official posts from you, I m mentioning you here )


Thank you.

schetz

Very nice analysis, meaningful post and bug report  . If only there were more posts like this here. 
As for your issue, I'm not entirely sure it's a software issue, as not all suffer the same problem, I'd say it's even a minority. 
I'm not having any issues using Nokia charger, but if I get a hold on another quick charger I'll try just to test.

In the meantime, have you tried switching cable? Or testing with another quick charger?

gowtham4us

Hi @schetz ,  Thanks a lot .

I ve tried switching cables and charger adapters. This happens in those too.

The only pattern that matches is "mA/sec > 1000 for more than 3+ minutes" (Mine was charging between 1400 and 1800. When its below 1000, no restart happening) .

Just google "nokia 7 plus charging restarting" and you can see more number of forums and discussions with the same issue.

Yes, this doesnt happens to many of the users. But the users facing this are in notable amount. And it is really a bad experience when we keep our phone on charge and it keeps on restarting every few mins. [ Think of a situation if no workaround available for this, Thank God ]


1 more suspect: My Android version is Oreo 8.1.0, Security patch 01-July-2018 and model TA-1046.

May be users with these OS version, model and Security patch are facing this ?

schetz

@gowtham4us I had no such issues even on Oreo. That will be an easy check though ,when you update to Pie. I hope it's resolved with that.

I'm still kinda afraid it's a HW issue.

Does AccuBattery show peak current history ? Is it possible there's a fault and the phone lets too much current, then other protection kicks in and resets the phone .

I used to use Ampere app, but as Nokia limits the charge while using the phone I'm not sure if there's a way to see peak charge in the app(need to wake the phone to see heh). And unfortunately I don't have device to measure without turning screen on. Now I'm sorry I didn't buy it back in a day.

I will try to check an app or 2 (primarily AccuBattery and Ampere) to see if I can get some log of charging current , or try to catch the peak current. Maybe you could try the same, if even possible, so we can compare.

Edit : actually scratch the app suggestion, only real comparison can be done by using USB multimeter , and we should agree to measure from same percentage probably.

gowtham4us

Hi @schetz , 

Yes, AccuBattery shows History too. You can give a try.

  Let me explain why I believe this is a SW bug and not an Hardware issue. Correct me if I m wrong anywhere.

Restart case:
1. Phone plugged to charger.
2. Screen turned off and Turbo charge starts.
3. After some 3+ minutes phone restarts.


Prevented case:
1. Phone plugged to charger.
2. Screen turned off and Turbo charge starts.
3. On 2nd minute, I ll just turn on screen (click lock button) and again turn off (just 1 sec).
4. It is not restarting for next few mins 
5. Continuing this screen ON for every next 2 minutes, the device will not restart. [ Did this for some 15 minutes ].
6. If I stop this screen ON , in the next 3+ minutes, it is restarting.
[ That 1 second screen ON and OFF prevents restart. I believe, that 1 second may not do any impact in hardware. What it will do is:  it will make the 1400+ mA/sec to <1000 mA/sec for that 1 second. Again this will reach 1400+ mA/sec anyway ] .


Hope you got the points. Else, let me explain in some other way.


Thanks.

schetz

@gowtham4us unfortunately I can't be sure you're wrong as I don't know the solution, otherwise I'd tell you
What I still think, is that you're effectively preventing phone going to full current charge and that doesn't mean you're preventing a software error. You do however limit the charging current by using inbuilt feature. 
And at the same time, if you're using a charger with lower output you don't need to prevent anything. 

Maybe the question is, what is actually protecting the device from getting too much current? Is it software protection, or is it some sensor as in hardware protection? Granted, it does operate on some low level "software" any way. 

Since my phone is at 97% now, I can't provide decent figure for comparison, but as you said AccuBattery provides charging current history, I'll install it and hopefully remember to write up the numbers tomorrow afternoon 
In the meantime, could you try charging your phone with quick charger and even let it restart, fire up AccuBattery and write down peak current, so we can compare tomorrow?

gowtham4us

Sure @schetz .

 I could understand the possible cases from your point of view. Let me try what you have suggested and share the data here. Thanks.

schetz

@gowtham4us absolutely non scientific AccuBattery numbers: max current with screen on appx 1810 mA, peak current with screen on (hopefully a delayed register of screen off) appx 3500 mA. 

manna

I think latest update can solve the problem...my phone now not get restart when charging...

gowtham4us

Hi @schetz, I've received Android P update yesterday and this has been resolved in Android P 😎. Also, Fast charging works even if screen is ON.

Thats so cool 😍

Thanks a lot for the concern 🙂

schetz

Awesome news @gowtham4us . I'm really glad an update saved you from repair centres or any other needless testing.

Steveooo30

My issue could be a little worse than everyone's, it restarted whilst Inwas actually using it and charging, if its shutdown and in safe mode. I manually updated to pie and 2 weeks later it started the reboot issue.
Only once whilst I was using it, so idk if it was just a fluke,maybe just picked it up at the point where it was gonna reboot.
Original charger tried and an easyacc 3.0 Qualcomm also,orig orig cable and aftermarket.
Anyone else with this issue being off and reboots let me know. Just hope its not hardware related.

METAL dev

Is this a bug in pie update????
Or a hardware problem???
Well I'm scared, it's a nice phone...
I was digging it...

guest19091993

Even I got the update then also this is happening restarts while charging.

HarshaTheStar

Nokia 7 Plus restarts while charging when I tried charging with Moto One Power charger it does not restart at all. Issue did not resolve even after many updates, poor support from Nokia.

HarshaTheStar

Nokia 7 Plus restarts while charging when I tried charging with Moto One Power charger it does not restart at all. Issue did not resolve even after many updates, poor support from Nokia.

Ranger49

My 7+ restart constantly while charging if I have raid of shadow legend or game of thrones conquest installed. These apps doesn't even need to be running. Installed is enough for my phone to crash. I retraced when my problems begun and uninstalled the apps I installed that day.

Ranger49

I currently have no games on my 7 plus. Hustle castle would also make the phone restart while charging. Background activity and performance should be more limited when it's fast charging. Nokia need to optimize the software more. I probably won't buy nokia again. Oneplus will probably be my next purchase.