How do I fix my S4 charge indicator that is stuck at 100?

[scalextrix]

S4 charge indicator stuck at 100%

I have a Galaxy S4 for about 18 months, I had some battery troubles and it turned out I had the dreaded battery bulge, no problem, Samsung replaced it for a new battery which is probably 2-3 months old now.
However Im seeing a strange issue, when I put my phone on charge last night it had 45%, when I got up this morning the charge indicator showed 100% - great. However when I unplugged the charge cable it then showed 69% - not so great. This has happened several times recently, on one occasion the battery was actually at 10%!!

It seems like the phone is charging up to 100%, then for some reason it stops charging, and starts using the battery, but the charge indicator is remaining at 100% even though its discharging, its kind of frozen.
I run an app called BOINC which uses the phone processor to do scientific research, and this will zap a battery, however my BOINC is configured only to operate when the phone battery charge level = 100%. I know this works properly.

So because the battery indicator gets 'stuck' at 100% even though in reality the charge is much lower, BOINC is crunching until I manually do something on the phone and get the battery charge indicator to 'unfreeze'.

I did a full reset of my phone yesterday (lost all my contacts), but it has not helped.

 

[srkmagnus]

Re: S4 charge indicator stuck at 100%

Are you using the charger and cable that came with your device? I would first check that since it seems like the battery is new.

Devices charge up to 100%, then often times stop charging then may start up again once battery depletes a few percentage points. But to see that it's at one time 10%, is a little concerning.

Let us know if the cable/charger are OK, or if a replacement fixed the problem.

 

[scalextrix]

Re: S4 charge indicator stuck at 100%

The AC charger is original, unfortunately the cable split so I had to replace it, but I bought what was supposed to be a genuine replacement part, however I saw there were comments about fakes on similar products at the online store.
My partner has a S4 Mini, will swap with that cable and see what happens.

 

[scalextrix]

Re: S4 charge indicator stuck at 100%

Unfortunately I dont have a definitive answer, charged on the other cable the first night and it was fine, charged on the replacement cable last night, also fine. The problem doesnt occur consistently.