Q: iPhone 5 temperature sensor problems

Hello there, gregory73

The following Knowledge Base article offers up some great information in regards to iPhone and acceptable temperatures:

iPhone: Hardware troubleshooting

http://support.apple.com/kb/ts2802

iPhone acceptable temperatures

• iPhone, iPad, and iPod touch (4th generation): Keeping device within acceptable operating temperatures

In that article we see that there are a number of things both externally and internally that can cause it to exceed the iPhone's temperature threshold. The article recommends these steps before attempting to use it after the warning screen has appeared:

To resume use of your device as quickly as possible, turn it off, move it to a cooler environment, and allow it to cool down.

If you find the issue persists, then the following is provided at the bottom of the Hardware Troubleshooting article:

My issue is still not resolved. What do I do next?

Contact Apple Support.

Thanks for reaching out to Apple Support Communities.

Cheers,
Pedro.