Just now, upon taking my iPhone 4 out of my pocket where it lives, I was faced with a screen saying "iPhone needs to cool down before you can use it" (see below - screenshot mysteriously still worked). The only thing it would let me do was dial emergency calls. The phone was not noticeably any warmer than usual when idle. Are there any known issues with this?

  • This is a non-answer, but this is a non-question: the only time I've seen it was when the iOS device sat in the sun for 45 minutes, and it was hot to the touch. Keep an eye on it and take it to Apple if it happens again. – Christian L Dec 1 '11 at 1:13
  • i have the same problem , i dont know what to do , i cant even charge it – user47317 Apr 12 '13 at 21:57

From the User's Guide:

If the interior temperature of iPhone exceeds normal operating temperatures, you may experience the following as it attempts to regulate its temperature:

  • iPhone stops charging
  • display dims
  • weak cellular signal
  • temperature warning screen appears

Important: You cannot use iPhone while the temperature warning screen is displayed except to make an emergency call. If none of the above measures succeeds in lowering the internal temperature, iPhone automatically goes into a deep sleep mode until it cools. You cannot make an emergency call when iPhone is in this mode. Move iPhone to a cooler location and wait a few minutes before trying to use iPhone again.

There have been numerous cases of all sorts of consumer electronics melting/exploding, and these have often been settled with lawsuits. It is appropriate that the iPhone take preemptive measures to avoid such accidents.

  • I completely agree, but my concern is that my phone was idle when I got the message and cool to the touch, so something was up. It hasn't happened since though so I'll just keep an eye on it. – Korneel Bouman Oct 11 '10 at 16:59
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    @Korneel: maybe you were observing the temperature after the phone took those measures to cool down. It might be extra cautious when that happens and maybe it waits until it is super cool before getting out of that mode. – Senseful Nov 8 '10 at 6:30

This happened to my brother's iPhone 4 a few times. When he took it to the Apple Store, they ran a special diagnostic that revealed the phone had reached 200 degrees inside. Needless to say, the phone was replaced.


This is a long shot but maybe there's a process going on in the background that's using a lot of processor cycles.

Consider double clicking the home button and quitting everything running and shutting the iPhone down, then restarting it.

Consider turning off bluetooth to see if that's an issue.

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    Double clicking the home button when all you see is the lock screen will not accomplish anything.. – please delete me Oct 19 '11 at 22:48
  • Double click the home button after waking up and unlocking your iPhone, hold down on the first app showing to get it shaking, click the "x" in the corner to delete it from memory. Restart iPhone. It's a long shot but worth a try. – Richard Oct 20 '11 at 9:19
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    You can't do that if you can't unlock the iPhone. Fortunately, the problem seems to be resolved for now. – please delete me Oct 20 '11 at 12:54

I left my IPhone in car's passenger seat while cleaning garage and had the same message when I retrieved the phone. It was a hot South Florida July day and the phone was hot to the touch. Took phone inside and after it "cooled off", started to work again as normal.


it is temp pin in battery just try to change your battery thats all

  • 1
    What is this supposed to mean? – bobbyalex Jul 8 '14 at 5:27

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