iPhone screen dims randomly

Check the attention aware features

https://support.apple.com/en-us/HT208245

Go to settings, general, accessibility, display accommodations and check that the “reduce white point” option is off.

As I said before, I contacted Apple and they said that it’s a feature to prevent screen burn in when the phone is hot.

Hi, this is very simple. All you need to do is go to Settings->General->Accessibility->Display Accommodations and you will see Auto-Brightness. You can also just search up Auto-Brightness in settings.

I have the same issue. I have the X 2 weeks and has happened twice. All power save settings are off. I only have True Tone on. First time it happened a week ago, I rebooted and it was fixed. The second time full brightness came back after a minute so I didn’t have time to react, I only checked my settings and all where off. When it dims it’s like it’s on 70% brightness. This has previously happened several times on my iPhone 6 and was always fixed after a restart.

I also believe that this is a heat related issue. It happens to me almost every day, but it always seems to be when the phone is connected to a charger, and specifically when the phone is warm to the touch.

Hey Anthony. I notice my screen dimming when my phone warms up a bit. My brightness will brighten back up when the phone cools down again. Perhaps it’s a safety thing the phone does to prevent overheating and exploding in our faces.

hi AnthonyAllstate, i think i found out the cause of the screen dimming down. ok if you want to get it fix go to to setting/general/accessibility/display accommodations, within here you should have invert colours off, colour filters off, auto brightness off and the last thing is reduce white point should be off as well. Try that out.

I have a solution for the diming screen problem: sort of.....I have my iphone attached to vent in my car. Its constantly cooling down by AC . No more problem. But I want to ask Apple what to do in winter time ,and, would Apple provide ice packs with Apple logo for summer outdoor use of that $1000 product to work as it suppose to?

It is a heat issue. Sunlight is not the problem for everyone. It has to do with load on the system. My first phone did it while gaming or being charged while in use. It was frequent and severe. My new one does it less, and it resolves faster. It rarely happens when it’s not charging. I do agree that Apple refuses to acknowledge it. That’s a problem.

I get this too, but I found a pattern to it. I think it’s not to do with temperature and everything to do with battery consumption.

I installed WWF Free Rivers on my X. It seems very processor intensive. My AR image looked jittery - the processor was under heavy load. I have an app installed that I can monitor load, it was very high.

Importantly the phone was not hot, it was warm but basically fine. I did notice however that in the space of 1 minute I lost 2% of my battery power.

I also noticed that although my screen brightness was set at 100% it was actually only 50%. I determined that by turning it up and down and noticed that it got brighter until it hit 50% and then didn’t get brighter as I increased to 100% - anyone else notice that? It’s basically being capped at 50% brightness.

So I put 2 and 2 together and come up with 22.

I think Apple are capping the brightness under heavy load in order to limit battery consumption.

Again my phone wasn’t hot. I’ve felt it get hotter especially in bright summer sun and it doesn’t dim when hot.

Anyone else come to the same conclusion?

As I mentionned before, this is a feature not a bug, to prevent burn-in in high temperatures and brightness levels.

I have the same situation with iphone 8 on the latest iOS. Auto brightness turned off, True tone could be off or on (doesn’t matter). So, brightness could by itself suddenly switch to 75% or lower, to 50%, however brightness setting set to max. It happens while gaming or watching youtube etc. Brightness switch from 75% to 100%, for example, doesn’t increase brightness, it stuck on 75%.

I have had such issue with my 6s and the problem was in certain iOS version, Apple released it last year for 6s to fix suddenly turn off issue (my iphone 6s was eligible for free battery replacement due to this) and there was a dependency with battery %. At 75% battery screen dims to 75% brightness, at 50% to 50% and so on.

Just now, writing this comment my iphone 8 was at approximately 75% max brightness and I couldn’t set it to 100%, it also was connected to the power from 60% battery, at the end of the comment iphone increased brightness to 100% 2 times and came back to normal, battery charged to 73%.

Considering this situation I can assume that this is iOS issue and made to prevent from overheating. I don’t like such approach, instead of doing everything well, Apple trying to fix the problems in a strange ways. Disappointed.

As indicated earlier in this post, go into Settings —> General —> Accessibility—> Display Accomidations and disable.

Go back to Settings —> Display and Brightness —> Disable True Tone if enabled.

Then, let your phone sit in your current lighting for about a minute. It will adjust. It doesn’t happen immediately.

I just purchased the iPhone X 64gb and that did the trick.

I have the same issue. Mine is always when the phone us under heavier load, like playing a game. It's worse when it's on the charger. It doesn't just dim once, like my iPhone 7+ did. It dims in stages, going from 100% to like 50% or lower in 2 or 3 steps. I am convinced it is a heat/safety feature, or bug. It's **** annoying.