Poor Battery Life in Lumia 920, 925

Windows Phone users, especially Lumia 920 and 925 users are facing a problem where they experience sudden battery drain for no apparent reason. It is due to stuck process where a process is stuck in the background and continues to use CPU cycles. Using Visual studio to do analysis we see that the phone OS is stuck at 50% and you get a warning of high CPU cycles.

Symptoms of the problem.

Overheating
Hot back plate
Left metal banding gets unbearably hot
Cannot charge phone as fast

To produce the problem again, follow these steps.

Put phone in airplane mode
Shutdown phone
wait 2 mins. and start up phone
once phone starts up you will realize phone is no longer heating up.
Put on a radio that establishes a data connection.
Os then gets stuck in a loop.
Phone begins to heat up.
Putting phone back in airplane mode does not help as the phone is now stuck. Following the steps above again will reliably reproduce the problem.

I have had my 920 replaced twice by AT&T and all three phones had/have the same problem – overheating and rapid battery drain. Needless to say, I’ve been following the issue closely. There are thousands of posts across multiple threads discussing this issue. Unfortunately, the problem is convoluted by the many possible variables; 3d party apps, core apps, settings, antennas, signal strength, GPS, background tasks, etc., etc. Yes it’s true that some apps may increase battery drain and yes, turning off some background tasks or location services may increase battery life, but this is not the battery drain problem plaguing the Nokia 920 and Lumia 925.

The 920 / 925 suffer from some sort of firmware/software loop which causes the CPU to overheat and rapidly drain the battery (10 – 20% per hour). The trigger seems to be any data connection. Third party apps may trigger the problem, but they are NOT the root cause. A factory reset unit (with only the base apps installed) will still suffer from the problem. The problem can occur while the phone is totally idle. Battery saver mode does not resolve the problem. Airplane mode does not resolve the problem. The only way to stop the loop/overheating/battery drain is to turn off the phone, let it cool down, then reboot.

Nokia and Microsoft refuse to acknowledge there is any problem.

  

About the Author

Kamaldeep Singh is the founder of Mytechpartner.com Kamaldeep chimes in every once in a while with some obscure news and interesting reads.

  • brhine

    Was searching the web because I was having the same issue. I can confirm that my new 925 does the same exact thing. Even after a factory reset with everything turned off, including all background tasks, except for the cellular antenna. I just replaced it on the 10th and this one is doing the same thing. Gets really hot just sitting on my desk. Takes about 6 hours to fully charge and discharges in about 4 1/2 hours on standby.

  • Rick

    Yep glad someone hooked the phone up to VS to examine the problem. 925 replaced 3 times third phone same problem

  • Graham Smith

    I’ve experienced this twice now, both times resorting to a hard reset to try and correct the problem. The second time, it didn’t work. After doing some searching I found someone complaining about voicemail not downloading into visual voice mail and it reminded me that I saw the same thing on my device.

    I went in to phone settings, switched it off, and restarted my phone and everything was fine. I later called my voicemail to find I actually had four messages, none of which had downloaded to my device. It must be getting stuck in some sort of loop trying to sync voicemail.

    I couldn’t care less about visual voice mail and I’m super happy I figured out what the problem was.

  • smiths

    Same thing happens on my phone. I ve done so many hard resets and even tried deleting some apps, no matter what the battery srains at lightening speeds even on stand by and you can fry an egg on my phone within 2 min of being on a call. I wish MS or Nokia would do something about this, its getting harder and harder to be a Windows phone fan.

  • MrWalrus

    We have ~50 of those at work, not one of them does is experiencing poor battery life. I’m not saying there is no problem, I’m just saying that this isn’t as universal to Lumia 920/925 as you make it sound.

  • elixer

    True, I bought it on the 7th got it replaced, and now its lying in the care center, they say we acknowledge the problem, but please use it till the new firmware update comes, it should fix it, although my phone is still lying at their care center.