Active Level 7

NOTE: This is an anecdotal workaround (or solution - whatever you wanna call it). I do not know the actual issue. A few weeks ago I was reminded of something and I tried it out, and it worked! This may or may not work for you. No guarantees.


Also, there is no risk involved actually but, if for some reason things go wrong, IT IS ON YOU. So proceed with caution.


Okay, all you need to do is to go to the recovery mode and, wipe the cache partition.

(Open: Instructions to open recovery mode and how to operate it)

Double...triple check that you have picked the correct option (Wipe Cache Partition) and nothing else. Do not be over-confident. Accidents happen like this. If you accidentally wipe data, it is going to be a sad day (for most). Trust me, it happens more than you imagine, even when you have to enter commands manually.


Technically, you do not need to do this (OTAs clear cache after successful installation - I reckon what and why of this can be found on AOSP documentation). Doing this manually does not have any benefit. However, there are times when things get mixed up and, something like this becomes helpful. So, you don't need to do this every single time. I have done this on almost every phone after an update that introduced some weird bugs or glitches. I used to perform this task since the earlier days of Android. It solved a few things, while it did not fix a few other things.


I faced the accelerated battery drain issue after the M307FXXU1ASJ1 update on 17th October. After using it for a few days I was reminded to wipe the cache. I did, and my issue was fixed.

The most recent update (...SJ2) on 30th October was totally fine.


I saw a lot of posts about the battery and I wanna say that...this phone has 99 problems but the battery ain't one. So a few points:

  • Do not compare battery life with equivalent Snapdragons. You will find many comparisons between similar classes of Snapdragon and Exynos. I have not seen comparison using the exact SoC used in M30s but in other comparisons, Exynos always consumes 5-10% more power (efficiency is totally different). There are a few differences. Check their spec sheets.
  • For 4000 mAh phones, 6-7 hours of screen on time is considered excellent. If you are getting around 10-11 hours of SOT then it is excellent! Play the number game, and keep in mind that it is using a bit more hungry SoC. (I know I know...I wish it had a Snappy inside but this one is not bad at all)
  • If you are crossing over a day/multiple days then consider standby power consumption. Adjust your expectations (hint hint: SOT will be lower for the same X% > Y%) based on that.
  • Stop clearing RAM every time you open the recent app list. Don't do that, unless necessary. Google for the reason...already a long post.
  • Don't fall for battery calibration habits.
  • Look for power-hungry culprits. Like some music players will consume more power in 1 hour with screen-off than 1 hour HD video playback on the web. Nuke/Restrict those apps. Report the issue with respective devs. Samsung Members app is one small example of that.
  • And if you are one of those people having network issues then you are out of luck. Don't blame the battery. Wait for a response from Samsung about the issue. Network hunting is going to consume more power. Do not try to force 4G. If your operator supports 3G then never force 4G. It's very likely that you will get better speeds than 4G as the 3G bands are freed up. I get better speed on 3G (10+ Mbps) compared to 4G (2 Mbps max at full strength - I do not have any network issue, in fact, I get 2-4 dB better reception).

Again, this phone has many issues. I'm not 100% satisfied. But the battery is not one. I hope wiping the cache will do the job for you. If not then...good luck!

Expert Level 5
mine works fine
Active Level 8
Your post is very insightful and luckily I dodged the last update( I would call it disaster update). For me, battery life is still average because of network issue ⚠️

I really appreciate your efforts to find an antidote for this battery drain issue 🤝

keep up with nice work like this ❤
Thanks ^^
I'd rather wait before updating from now on. I trusted and updated immediately because Samsung has a good track record on average. This workaround is not guaranteed & I wouldn't count on it to help with anything. Now I heard about A50 update fiasco. From now on I'm gonna wait for at least a few weeks before updating. I'm lucky that it did the job for me.

I saw your posts about network issues. Did anyone respond for further clarification?
yes, as usual charade from Samsung, their team lead will call you and suggest you to take the device to ACC and they will do a factory data reset. But even all this maze everything is back to square one 😤

They have to push an OTA update to fix this issue but I don't know why they hesitating these much.
Active Level 10
I agree, battery life on M30s is actually good. I do have problem with the build quality and the camera but other than that this phone works fine for me.

Although, I'd like to point out that this method that you have posted won't remove the security patch. If you are saying that the update has caused this issue then you should flash the previous ROM that may remove the security patch and the update that was applied.
Nah. I'm not saying that this will remove anything. This is just for deleting old cache files that might be conflicting with newer system apps.

All I'm saying is that sometimes old cache files are left behind after a successful update for some weird reason. These files may affect updated system apps. Usually it's battery drain or App Closing Pop ups. Wiping cache partition clears this conflicts if there are any.

This is a minimal risk 'hope for the best' kinda trick. That's why I said, it won't work for everyone.
That is true, wiping the cache partition clears such conflicts. Hope it helps others to resolve their issue.