A portable terminal device and method thereof includes a main power supply to supply electric power to a system part of the portable terminal device, a wireless transmitting/receiving part to wirelessly transmit/receive RF signals through a network, the portable terminal device includes an indicator, an auxiliary power supply, and a micro controller determining whether a wireless connection to the network is possible by analyzing the RF signals, and controlling the indicator to indicate an analyzed result of the RF signals. A power controller controls the auxiliary power supply to supply electric power to the indicator, the micro controller, and the wireless transmitting/receiving part when the electric power is not supplied from the main power supply and the wireless connection to the network is possible.