Short form of radio frequency identification also called as dedicated short range communication (DSRC) technology. RFID is used to explain many technologies that are used in radio waves for automatic identifications. RFID works as bar code identification systems however the difference between RFID and bar code technology is that RFID does not depends on the line-of-sight reading that bar code scanning requires to work. Radio-frequency identification makes use of an RFID, tag applied to a product, animal, or person for the purpose of identification and tracking by using radio waves. Almost all RFID tags have two parts. IC for storing and processing information and antenna for receiving and transmitting the wave. This mobile car unit system using RFID technology is supported by using ARM 7 based microcontroller.