Help wakelock detector for unrooted phones?

[cdl]

I have an unrooted dual sim Motorola Moto G 2nd generation, running Android 5.0.2.
Battery life has become ridiculous: even with minimum usage I have to charge 2-3 times a day. My other phones have always been rooted and I used apps like wakelock detector and better battery stats to find which apps were preventing the phone from going into sleep mode. How can I do the same on my unrooted Moto G? I don't want to root it now because it would void the warranty, and there's a chance I might have to send it to tech support if the battery really is faulty.

 

[Thom]

Did you Wipe Cache Partition (deleting all temporary data and not touching any germinate data)?

Did you try running in Safe Mode (disabling all apps you added without uninstalling them)?

... Thom

 

[cdl]

Did you Wipe Cache Partition (deleting all temporary data and not touching any germinate data)?

Did you try running in Safe Mode (disabling all apps you added without uninstalling them)?

... Thom

I'm not sure I can delete the cache partition unless I'm rooted. I tried rebooting to safe mode but nothing changed. The only thing which helps is restricting background data: only if I do this does the phone go into sleep mode.
I guess I need root to figure out what app is causing the phone to always stay awake; however, since the same problem happens even when rebooting into safe mode, it must be a system app

 

[Thom]

I don't have your phone. This is from the Motorola website ...

How do I clear Cache Partition on my device?
This will remove any temporary files that may be causing the problem, but will not delete your files or settings.
1. With the phone powered off, press the VOL DOWN KEY for 2-3 seconds then POWER key then release.
2. The device will display different BOOT OPTIONS
3. Use the VOL DOWN Key to SCROLL to Recovery and VOL UP Key to select
Tip: If the device reboots, you may have waited to long to make a selection, you will need to begin the process again.
4. The device will display the Motorola logo and then the Android in distress ( logo with Exclamation mark)
5. Press and hold the VOL UP key for 10-15 seconds. While still holding the VOL UP key tap and release the POWER key
Tip: You can try this step, holding the phone in landscape. If you are stuck on step 6, try a force reboot by pressing the Power key and Vol Down key, and start the process again.
6. The device will display additional menu options (Text will appear in BLUE)
7. Use the VOL DOWN Key to scroll to wipe cache partition and the POWER Key to select this option
8. The device will then perform the partition wipe
9. The device will reboot and start the normal power up sequence

... Thom