The first troubleshooting step I recommend to analyze your Nexus 6P is to boot the device into Safe Mode and see if the culprit is a 3rd-party application.
The Android OS gives 3rd-party applications quite a lot of liberties when it comes to what they can or cannot do with your phone. Google is attempting to prevent unnecessary wakelocks with Android 6.0 and its new Doze feature, but an application can still force your device to wake up if the notification is marked as critical.
Google says they will prevent apps from abusing this, but we’ll see how that goes over the next few months. Still, 3rd-party applications can cause more issues than just poor battery life.
If an application(even one that is in the background) can cause the CPU and/or GPU to be ramped up to the maximum clock speed. Not only will this cause poor battery life, but it will also cause the device to heat up way too much. This could force the kernel to reduce the maximum clock speed and then this would cause sluggish performance on your Nexus 6P. Some of the time these issues arise from poorly optimized code but they can also be caused by a bug(like corrupt cache data or something).
Either way, I would say that 3rd-party applications contribute the most number of issues that people generally experience on their Android device. This is why I recommend people try things out in Safe Mode to see if that fixes the issue. So let’s talk about how to boot the Nexus 6P into Safe Mode.
Nexus 6P Safe Mode
- Have Your Nexus 6P Powered on and at the Home Screen
- Then Press and Hold the Power Button
- When You See the ‘Power Off’ Dialog Screen Pop Up, Let Go of the Power Button
- Then Tap and Hold Your Finger on the “Power Off’ Option
- After Holding for a Few Seconds You’ll be Asked if You Want to Reboot Into Safe Mode
- Simply Tap the ‘OK’ Option to Reboot Your Nexus 6P Into Safe Mode
- Then Wait for the Nexus 6P to Reboot
Booting the Nexus 6P into Safe Mode is going to temporarily disable any and all 3rd-party applications on the device. These will only be disabled while in Safe Mode, so when you reboot the Nexus 6P again, you will go out of Safe Mode and these applications will work like normal again. While in Safe Mode, applications can not be opened and the simply will not work(even in the background). This can be troublesome but it is necessary in order to find out if a 3rd-party application is causing the battery life, performance, overheating or whatever other issues you are testing for.
So, to boot the Nexus 6P into Safe Mode, we need to hold the Power button down as if we wanted to turn off the Nexus 6P. This will bring up the dialog box with the ‘Power Off’ option that you can tap to turn off your Nexus 6P. Instead of simply tapping this button, you’ll want to tap and hold your finger down down this Power Off option. After holding your finger here for a few seconds, you should see this dialog box disappear and then a new dialog box will appear. This new box is a prompt asking if you are sure that you want to reboot the Nexus 6P into Safe Mode. So go ahead and tap that OK option and your Nexus 6P will reboot and you’ll be in Safe Mode with a watermark at the bottom right.
As mentioned, while in Safe Mode, you will not be able to launch of use any 3rd-party applications that were downloaded from the Google Play Store. Core applications like the Dialer application will work, so at least you’ll continue with a functional smartphone. It is recommend that you try out Safe Mode for as long as needed. If you are experiencing poor battery life throughout the day, then you should try out Safe Mode for a full day. This should give you some data(like a certain amount of battery drain after so many hours) and then you can compare this with how your device typically behaves.
If you are having overheating issues, then monitor the temperature of the Nexus 6 while you are in Safe Mode or while you are doing things like playing video, recording video, browsing the internet(or anything else that you typically see the device heating up while doing). The same thing goes with performance too. If you had noticed issues with lag during certain moments of the day(or when doing certain things) then try to replicate those tasks while the Nexus 6P is in Safe Mode so that you can figure out if there is a 3rd-party application causing the issue.
When you’re done with Safe Mode, hold the Power button down and tell the Nexus 6P to turn off. Then turn it back on but don’t hold down any Volume buttons during the boot process and you’ll be taken directly back into the regular Android OS. If you have determined that a 3rd-party application is the root cause of the issues you are having, then the next step is to uninstall some apps until you find out which one it is. There is no easy way of going this other than trial and error.
If you experience the same type of issues while you are in Safe Mode, then there is likely an issue with the core Android OS. The next step would be to wipe the cache partition and if that doesn’t help then to do a full factory reset on the Nexus 6P.