Apple has a lot to say on the subject of heat, saying that the iPhone (and iPad, iPod, and Apple Watch) operate best at 32° to 95° F (0° to 35° C), and warns that it is “especially important to avoid exposing your device to ambient temperatures higher than 95° F (35° C), which can permanently damage battery capacity.” Now, Apple has had a mechanism built into the iPhone that kicks in when the device gets too hot, but it seems that with iOS 16, the company has taken this further. This is mentioned in Apple’s support page about maximizing battery performance, which says that “software may limit charging above 80% when the recommended battery temperatures are exceeded.” What’s not mentioned here is that when this happens, you will receive a Charging On Hold notification. Also: Using your iPhone in high temperatures can cause permanent damage The notification states that Charging will resume when the iPhone returns to normal temperature. There’s also a message that can be found if you tap on Settings > Battery: Once charging has resumed, the message changes to Charging was on hold due to iPhone temperature. So, the Charging On Hold notification is normal, and not a bug. In fact, it’s a mechanism that helps prolong battery life. So, what should you do if you see this message? Well, you have a few options. You could just let iOS 16 and your iPhone do its thing. Apple has you covered, and charging will resume when it’s safe to do so.

How to cool down your iPhone

Alternatively, you could take steps to cool down your iPhone. These include:

Moving the iPhone to a cooler location.Removing the iPhone from its case.Lowering the brightness of the display.Stop running power-intensive apps while it is charging.Put the iPhone into Airplane Mode.

Something that I do find odd – and I’m not sure if it is a bug or a feature – is that the battery indicator at the top of the display continues to show the battery as charging.  It’s a mixed message that adds to the confusion. So, if you see this message, rest assured that it is normal, and your iPhone is working to protect your battery from damage and prolong its life.