A method of performing a random access channel (RACH) procedure between a mobile terminal and a network includes the steps of detecting whether a random access response (RAR) is received from the network within a certain time period, the RAR including information about a random access channel (RACH) preamble transmitted to the network; and if the RAR is not received within the certain time period or if the information about the transmitted RACH preamble included in the RAR does not match the transmitted RACH preamble, performing a first procedure to detect failures in the RACH procedure; and if the RAR is received within the certain time period and if the information about the transmitted RACH preamble included in the RAR matches the transmitted RACH preamble, performing a second procedure to detect failures in the RACH procedure.