After report surfaced that Apple’s new iPhone 3GS had problems with overheating, followup articles point to the batteries being the source of the problems:

Vronko said the iPhone 3GS’s heat problem is evidently tied to the battery, because the pictures of discolored white iPhones reveal the outline of the battery. He noted that although thousands of iPhone 3GS users probably own defective handsets, the risk of causing fire or explosion is low because the iPhone’s battery cell is extremely small.

I decided to do a small test and played two rounds of Star Defense on the phone while on Battery power. Here’s what I found using an infrared thermometer. Initially, ambient temperature of the room was 80°F and the iPhone measured 83°F on the back. After playing the game, the room temperature had dropped 2° to 78°F while the iPhone 3GS measured 102°F on the back. More interestingly, there was a temperature gradient:

I’ve also felt the phone get much hotter than this quick test, probably proportional to how much load you put on its battery. There’s an Apple support document called Keeping iPhone 3G and iPhone 3GS within acceptable operating temperatures which documents some obvious “leaving your phone in the sun” cases which can cause overheating:

- Leaving the device in a car on a hot day.
- Leaving it in direct sunlight for extended amounts of time.
- Using certain applications in hot conditions or direct sunlight for long periods of time, such as GPS tracking in a car on a sunny day or listening to music while in direct sunlight.

One Response to “iPhone 3GS Too Hot Temperature?”

1. Wendy says:

   7/6/2009 at 12:44 am

   The curious bird with an experimental heart!!^o^

   Reply