Strange charging behavior. Intermittent charging, until rebooting

[RedOctobyr]

I ran into something odd with my Verizon G4 last night. Before going to bed, I put it on the same old AC charger that I've used for years with my Galaxy S3. It's old, and probably low-current, but I've never had a problem with it.

This morning, my phone had only increased from 15% to 44%. Very strange. And when I looked at the graph from overnight, the charge level looked like a series of bumps and dips. It would climb, then drop, then climb, then drop, each time getting a little higher. I assumed maybe the old charger couldn't supply enough current and was overheating and shutting down?

So during the day I tried some other chargers. Same result using a cheap eBay one. The battery icon would show charging, but the graph would show the charge level going up and down, and barely making any progress. Borrowed a Samsung charger, *still* no better.

I noticed that the phone was sometimes rather warm, right around the camera. I started wondering if the phone was overheating, and throttling-back the charge current, perhaps.

It finally occurred to me to try the obvious: reboot. I rebooted the phone, and it was immediately fine. It stayed cooler, and the charge level steadily increased, still using that same Samsung charger.

The phone had been factory-reset on Friday, then I transferred my apps & data from my old phone, upgraded a bunch of apps, etc. Unfortunately, before rebooting, I did not try to figure out if something specific was causing trouble. I don't see the Task Manager that I had on my S3, so I'm not currently sure how to look for an app using a lot of CPU time.

My current theory is something was "stuck", and was drawing a lot of CPU cycles, making the phone warm. This made the battery discharge faster, and I do also think something (charge current? Or, conversely, CPU speed?) was being throttled up/down, as the charge level kept going up and down, even with the charger still connected.

See attached screenshots. The first was overnight. Up/down/up/down. The second is during the day, WiFi off, GPS off, trying different chargers. I'd leave each connected for a while, but the charge level kept going up/down (the smaller spikes/dips you see). The last shows when I rebooted in early afternoon, then the charge level climbed normally after that.

So if you see a weird charge log, try rebooting. This makes me curious what happens if you run an intensive benchmark, making the phone warm, while trying to charge.

 

[belodion]

Thx for sharing and glad you've got it fixed.

Posted via the Android Central App

 

[RedOctobyr]

This is old news now. But a few days after my original post, my phone actually *discharged* itself overnight. Screen off, plugged in, the charge level dropped from about 55% to 22% overnight.

I now believe this is due to a heat issue. Something (an app? system process?) was presumably "stuck", and running too much overnight, warming the phone up. As the phone warms up, it reduces the charge current.

You can see that the graph of battery % goes up/down/up/down all night. My assumption is that the graph would go up, until things got too warm, then the phone would reduce the charge current. The temps would drop, as would the charge %. Then the cycle would repeat once the phone cooled off.

The Battery Monitor Widget screenshot shows the same battery graph, but also shows evidence that the phone was plugged in/"charging" all night, with the screen off. The outlet wasn't turning on/off, or anything like that.

For testing correlating charge current and phone/battery temperature, see this thread:
http://forums.androidcentral.com/lg-g4/540551-slow-charging-apparently-related-temperature-warm-slow.html

 

[belodion]

Thx for the update.

The sawtooth effect is similar to something I saw once on my Lumia 1020, which was draining battery inexplicably. Mine wasn't up-and-down like yours, but flat-down-flat-down, in tiny steps. I eventually tracked it down to something trying repeatedly to update.

I also once experienced a spectacular overnight drain, on my other Lumia in fact, a 930, which fell from 96% to 3%....in fact it had powered off in the morning to protect the battery. I still don't fully understand that one, though there was a partial possible explanation to do with an unclosed app, despite settings to the contrary.

All very interesting stuff but sometimes frustratingly difficult to understand.

Posted via the Android Central App