This message appears when an iPhone 3G or 3GS becomes too hot.
[ Photo courtesy of Apple ]

PC World, Wired, and other media outlets have reported that the new iPhone 3G S models have been running a little hot—hot enough to turn their white plastic cases brown, according to Wired  .
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Apple Support has acknowledged an overheating problem with both the 3G S and 3G phones, when they "run 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."

This problem may be limited to specific lots of phones, as such problems have not turned up during our tests, which are still ongoing.

Besides feeling hot, symptoms of an iPhone suffering from heat exhaustion may include a dimming display and a weak cellular signal. The most-obvious sign is an on-screen message "iPhone needs to cool before you can use it" (see image at right).

We'll keep you posted as the story unfolds. In the meantime, please let us know if you've experienced an overheating problem with your phone. —Mike Gikas