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MightyTrojan

macrumors newbie
Original poster
Sep 16, 2014
27
12
Cupertino
I don't like the auto-brightness feature so I turn it off all the time. However, I noticed something strange tonight that the screen actually dimmed itself a little bit, and if I want to go back to full brightness, I had to restart the phone.

Does anyone know if this issue is hardware-related or software-related?
 
We would need more specifics.

You mean you have auto-brightness turned on, went into a dark area so the phone dimmed, then you somehow couldn't use control center to adjust the brightness back up? :confused:
 
We would need more specifics.

You mean you have auto-brightness turned on, went into a dark area so the phone dimmed, then you somehow couldn't use control center to adjust the brightness back up? :confused:

You didn't even read what OP wrote, he's pretty clear what he meant....:rolleyes:

Anyway, can't say for 6+, but my 6 works fine in terms of back light, there is no issue of dimming.
 
You didn't even read what OP wrote, he's pretty clear what he meant...

To you perhaps, sure wasn't clear to me why he didn't simply use control center to put the brightness back up instead of restarting the phone.

Guess anyone who asks a question to clarify before trying to help should get a roll of the eyes eh? Nice world with wonderful people we live in...
 
We would need more specifics.

You mean you have auto-brightness turned on, went into a dark area so the phone dimmed, then you somehow couldn't use control center to adjust the brightness back up? :confused:

No. I turned that feature OFF because I prefer to adjust screen brightness myself through control center.

After the phone dimmed itself, I tried to turn up brightness in the control center. Unfortunately, it DIDN'T work. It would not go back to original brightness level.

Normally, you would see screen become brighter as you turn up brightness, but in my case, when I turned brightness from medium to maximum level, the brightness doesn't change anymore. It only changes when it's in lower level of brightness.
 
No. I turned that feature OFF because I prefer to adjust screen brightness myself through control center.

After the phone dimmed itself, I tried to turn up brightness in the control center. Unfortunately, it DIDN'T work.

Normally, you would see screen become brighter as you turn up brightness, but in my case, when I turned brightness from medium to maximum level, the brightness doesn't change anymore. It only changes when it's in lower level of brightness.

Wow, that is very weird. If I had to guess that would simply be a random bug with iOS 8. After you restarted your phone can you replicate the issue again and again?

Thanks for the additional clarification btw.
 
Wow, that is very weird. If I had to guess that would simply be a random bug with iOS 8. After you restarted your phone can you replicate the issue again and again?

Thanks for the additional clarification btw.

I had similar issues with my 5s in the past, and I didn't really give extra attention to it. But I can't believe this issue still exists now. Disappointing.

I can't really replicate the issue as I don't know when it will dim. It's very random.

I already restored the phone by downloading brand new OS from iTunes, and after installing and playing with it, the issue reappeared again.
 
I had similar issues with my 5s in the past, and I didn't really give extra attention to it. But I can't believe this issue still exists now. Disappointing.

I can't really replicate the issue as I don't know when it will dim. It's very random.

I already restored the phone by downloading brand new OS from iTunes, and after installing and playing with it, the issue reappeared again.

Sucky :(

Wish the error was more consistent (even though that would be bad as well) so it would be fixed by Apple or you could replicate it to a genius to perhaps get a new phone. If you've already restored through iTunes I would just make sure it's not from a backup and simply start fresh to see if the issue still occurs. One time I had an overheating problem with my 4s, restored from backup though iTunes and had the issue pop up again. Once I did a completely clean restore it fixed whatever issue it was and I never saw it again.

I personally have never seen that happen on my 5s though.
 
I have the exact same random problem and it is driving me crazy! Any luck finding a solution?
 
It happened to me too. I think it happens when the phones gets hot. As soon as it cools down a little bit the brightness goes to maximum again.
 
If it's the same as the iPhone 5S, it's probably overheating... My phone tends to dim itself when it gets too hot.
 
It is 100% a product of overheating. My 6 did it too and my 5. My 6 plus doesnt though.
 
My 6 Plus also seems to dim randomly - auto brightness is also off. It always when it's been sitting around for a while, so I'm not sure it's a heat issue.
 
Its purpose is to kick in when the iphone is over heating. If yours is cutting in randomly then your device is faulty, its not normal
 
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My 5s did that a lot and now my 6 plus (both on iOS 8). On 6 Plus, it happens a lot when I play Modern Combat 5 for a few minutes. First, it dims to about 75% then a few min later to about 50%. I'm not playing the game outside in the hot sun. It's in a air conditioned home. I do notice it getting hot when it happens so it's likely an over heating issue. Surprised it's not happening to more people. Hope Apple fixes it soon. dont know if it can be fixed via software update.
 
Mine too. Driving me bats. Dimming screen is self-generating and random. Can't be reproduced on command but happens everyday. No apparent association with "heat" -
my iPhone has never show signs of heating up unless battery is being recharged. The dimming occurs both when power cord is attached and when running only on battery. Which suggests software issue rather than hardware (but I'm not an engineer...)
 
Been having this same problem myself as well and it's driving me insane. I thought I was crazy for the longest time, until I was able to capture it on video.

https://vid.me/Vtb

Dims at 4:55, brightens at 6:20

From my experience it seems to happen primarily when playing games or watching videos in Safari. It's quite random when it happens, but after it does the brightness will pop back after around a minute or so

I'll be going to the Genius Bar tomorrow, so I'll be sure to report back.
 
Funny you posted this today.

I live in Florida and it was pretty sunny and hot yesterday. I was using my phone outside in direct sunlight, and the screen definitely didn't seem as bright as it is most of the time while using it in the bright sun here. I would say it felt as if the brightness level was almost at 50%. This was around 2pm in the afternoon and I just attributed it to the sun being a little brighter than normal or something strange. Didn't check my brightness level.
 
Happened on my 4S couple of times.. i noticed it was hot then the screen dimmed..

this happened like 2 months ago and i remember the brightness bar was on the highest level..
 
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I've also had this happen with my iPhone 5 when it got overheated. For me, that happened mostly when using the GPS functionality in the car. Sucked that GPS usage could cause the phone to get so hot, but since it was one use case I didn't get too worked up about it.

If the newer phones (and it sounds like maybe the 6+ in particular) are prone to overheating when doing things that the older iPhones would not overheat from, I'd consider that to be a pretty big issue. Hopefully it's something specific to poorly written apps and can be fixed via better software.
 
I can understand this if a device is being strained to it's limit while in a warm environment, though even then I'm not sure how much heat difference turning down the brightness would make.

That said, this seems to happen when doing simple things like watching MP4 videos, or even browsing Safari at times. It's also far from warm weather where I am.
 
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