Relationship between boot loop manufacturing defect and battery life problems?

[WarER4X]

Search though the G4 section of this forum and you'll find a few threads where I was dealing with battery issues with my phone. Being an engineer, I tried every test/experiment I could pull off to isolate the problem and was unable to come up with anything other than it being a hardware issue after several months of trial and error with settings, apps, usage, you name it.

Verizon Customer Service saw things my way and decided to replace my phone (under warranty, of course). The replacement phone seemed marginally better, but still suffered from similar problems as before. In particular, it would exhibit random instances of large battery drains (usually attributed to Android system-level processes by GSam battery monitor). Also, like the previous phone, it would occasionally get warm in my pocket without even being used (when it should be on standby). GSam monitor graphs seemed to show some correlation with cell signal, but not consistently and it was just as much influenced by screen-on time, making it difficult to tell who the real culprit was.

The Marshmallow update came along, with "Doze Mode" on board. This helped the standby battery life noticeably (like if I'd walk away from my phone at home and come back three hours later), but the times my phone actually went into "Doze" weren't often enough to really help with overall power consumption. I pretty much just lived with it. I got into the habit of charging my phone at work every afternoon just to be sure it wouldn't die before bedtime.

Fast forward to about a week ago... My phone succumbed to the dreaded G4 "Boot Loop" issue, which - according to the intarwebs - is the result of a manufacturing defect related to the "Big" processor cores which are used by the phone for all of the heavy lifting. Again, my phone was replaced under warranty. I loaded everything back onto the replacement device and went on with my life. I was not expecting to see any other differences, but I did...

To start with, under normal use, my average battery drain has dropped from ~6%/hr to ~3.5%/hr, when screen-on time is nearly identical to what it was with the previous phones. This is a real, measurable difference in battery life. Additionally, I have noticed that my screen-on time can go well over 2.0 hours and still have >50% batter life left. That was basically unheard of on my previous G4's. My usage, settings, apps and location are unchanged, but the phone is working more efficiently. I have also noted that the max temperature reported by GSam since getting the replacement phone as not exceeded ~95 degF. The old phones would regularly get to 104 degF and even higher at times. I don't even think I've seen the replacement reach 100 degF yet. I also have not had it get warm in my pocket like the others did.

So, how could this be? It got me to thinking... what if that "Big core" mfg defect that can lead to boot looping can also result in processor inefficiency up until the point when it fully fails (and creates the boot loop). Could it be that those "Big" cores were working harder than they needed to in order to compensate for date transfer errors internally, or perhaps a trace or circuit connection was not fully formed and lead to more resistance in the signal, generating more heat (lost power)?

I can't say for sure. You decide...

-SR-

 

[bayouguy71]

Serial numbers on old devices vs. new device?

 

[steveathome]

That's exactly what I want to know. As I mentioned on another thread, I have been on the verge of getting an unlocked G4 but was and still am holding off a purchase as it was mentioned by someone that they had just bought a G4 with a 602 serial number and it had the bootloop issue after two days.

 

[TNCattleDog]

Knocks on wood...

I think you are on to something. Granted there are several of us that post here regularly so I cant really get a general sampling, but is seems like a lot of the people who have posted in the boot loop threads are some of the same that have posted in the poor battery life threads. Again, some are dedicated posters who come here often so its hard to get a true sampling..

That said, I have had very good battery life on my G4 that I got right after launch. Battery has significantly improved for me on MM and I (knocks on wood again) haven't had boot loop issues.

David

 

[tardus]

That's exactly what I want to know. As I mentioned on another thread, I have been on the verge of getting an unlocked G4 but was and still am holding off a purchase as it was mentioned by someone that they had just bought a G4 with a 602 serial number and it had the bootloop issue after two days.

There were over 1,000,000 G4's sold in the first three months that it was offered. That was ground zero for bootloop problems. Look at the forums - the number of complaints. I think the failure rate that many of us here assume to be true is massively overestimated. Like I've said before, I think 25% failure rate for 505-508, and that number (25%) is likely way too high. You can't look at anecdotal evidence and draw an accurate conclusion. Reports of a handful of outliers beyond the expected range isn't so significant imo. I'd love someone with access to actual numbers to weigh in. Maybe an LG employee or even an employee of a carrier store with access to the data. Until then we're just guessing.

I believe that there are bad manufacturing runs. So someone gets 3 G4's for a family and 2 bootloop. It doesn't mean there's a 66% failure rate.

@WarER4X - interesting but we need some other G4 owners to weigh in. One single data point isn't enough to draw conclusions. I understand you're throwing the idea out there. And you may be right.

 

[Mikey47]

Maybe an LG employee or even an employee of a carrier store with access to the data. Until then we're just guessing.

I believe that there are bad manufacturing runs. So someone gets 3 G4's for a family and 2 bootloop. It doesn't mean there's a 66% failure rate. .

I'd love someone with the actual numbers to weigh in too, but I doubt we will ever get it. But given the press attention that was given when LG admitted the issue says that the numbers were pretty high.

We got two G4s in our family and both ended up with the boot loop issue - that must mean 100% were affected, right?

 

[Wdib]

Hi.

I also experienced the Boot Loop drama, and when I sent it for repair, it turned out that my motherboard was damaged and required replacement.

Once replaced, my phone was alright again until last week. As soon as I updated to the Marshmallow 6.0, I've experienced sever battery drops (requiring me to charge my phone constantly).

My phone also heats up randomly when not being used. When I checked battery usage in the settings, it informed me that Pocket (app) had been using 27% of my battery's power.

I then tried a hard reset, switching off 4G AND GPS, as well as autobrightness and battery saver.

There's a thread on this forum discussing the Pocket problems, and I've since then uninstalled it.

Conclusion: My phone is still dicked. I love the UI, and the way the phone looks. But my experience has not been positive so far. I'm just going to sell it for less than half price.

 

[tardus]

Hi.

I also experienced the Boot Loop drama, and when I sent it for repair, it turned out that my motherboard was damaged and required replacement.

Once replaced, my phone was alright again until last week. As soon as I updated to the Marshmallow 6.0, I've experienced sever battery drops (requiring me to charge my phone constantly).

My phone also heats up randomly when not being used. When I checked battery usage in the settings, it informed me that Pocket (app) had been using 27% of my battery's power.

I then tried a hard reset, switching off 4G AND GPS, as well as autobrightness and battery saver.

There's a thread on this forum discussing the Pocket problems, and I've since then uninstalled it.

Conclusion: My phone is still dicked. I love the UI, and the way the phone looks. But my experience has not been positive so far. I'm just going to sell it for less than half price.

Pocket isn't optimized for Marshmallow. You can't hang that on LG. It takes a phone some time to get optimized under a new release. Unless you hate the G4 give it some time. Reaching out to Pocket developers might something to try.

 

[sswitzer]

Hi.

I also experienced the Boot Loop drama, and when I sent it for repair, it turned out that my motherboard was damaged and required replacement.

Once replaced, my phone was alright again until last week. As soon as I updated to the Marshmallow 6.0, I've experienced sever battery drops (requiring me to charge my phone constantly).

My phone also heats up randomly when not being used. When I checked battery usage in the settings, it informed me that Pocket (app) had been using 27% of my battery's power.

I then tried a hard reset, switching off 4G AND GPS, as well as autobrightness and battery saver.

There's a thread on this forum discussing the Pocket problems, and I've since then uninstalled it.

Conclusion: My phone is still dicked. I love the UI, and the way the phone looks. But my experience has not been positive so far. I'm just going to sell it for less than half price.

Most likely a fairly simple app problem. Personally I had issues city pocket and AccuWeather; I found the issues through gsam. Since getting rid of those two my marshmallow upgrade has been great.