A communication module in a vehicle according to an embodiment of the present invention comprises: a battery unit; a receiving unit for receiving power from the battery unit and operating by a predetermined period in a reception standby state; and a control unit configured to accumulatively calculate an amount of current consumed according to an operation time of the receiving unit, and generate a control message for controlling a turn-off of the communication module or controlling an operation period of the receiving unit when the accumulatively calculated value exceeds a predetermined value.