Although there has been no official admission of an overheating problem, the warning at least acknowledges that there is a problem. Who does Apple blame however? You, the iPhone 3GS owner.
The warning says that the phone is not meant to function properly if the temperature is above 113 degrees Fahrenheit and tells users to not leave the phones in parked cars.
Says the warning: "If the interior temperature of the device exceeds normal operating temperatures, you may experience the following as it attempts to regulate its temperature: the device stops charging, display dims, and/or weak cellular signal."
You should probably listen, if you don't want the dreaded Temperature Warning screen:
