

Generally, extremely high temperatures are harmful to electronic devices. This is especially true when they are charging because that process generates heat. If your iPhone, more specifically its battery, gets too hot, bad things can happen. These may include swelling or internal damage to the battery. This can reduce the lifespan and longevity of the battery.
With iOS 16, Apple introduced a system that pauses iPhone charging if the device gets too hot. This way, the operating system can attempt to maintain safe charging for the health of the battery and your safety. When this process starts, iOS 16 informs you that it is pausing charging until the temperature returns to normal.
You will see this most often when driving. Many of us plug our iPhones into the car to use CarPlay and place our devices on the dashboard. This means your iPhone is near the windshield, sitting in direct sunlight, or maybe you just plugged it in and it’s resting in a particularly hot part of the car.

What to Do When You See the “Charging On Hold” Warning
Basically, you just need to let the temperature of your iPhone cool down to a safe level. Apple recommends keeping the ambient temperature around your iPhone between 16ºC and 22ºC.
Of course, this takes time, but there are some ways to reduce the time you have to wait to charge again.
The first thing you should do is safely pull over if you are driving. Remove your iPhone from direct sunlight. You may also want to take your device out of its case as that will help the device cool down faster.
If you want to speed up the cooling process even further, here are a few things you can do. However, please note that many of these will prevent you from using your iPhone for navigation or listening to music.

– Lower the screen brightness or use Auto-Brightness in the Accessibility settings
– Enable Low Power Mode
– Turn on Airplane Mode
– Turn off your iPhone for 10 to 15 minutes
Along with any of these, you should keep your phone out of direct sunlight. Another step you can take is to stop any apps that are using mobile data.