A mobile device detects whether its temperature is within a first or second range of values, and operates in a full communication state within the first range and a limited communication state within the second range. The mobile device receives a communication request for establishment of a voice call or for communication of a user data message. In the full communication state, the mobile device permits an emergency or non-emergency voice call to be established, and permits a user data message to be communicated. In the limited communication state, the mobile device inhibits a non-emergency voice call from being established, but permits an emergency voice call to be established.