A mobile terminal comprising: a main body; a display; a component module coupled to the main body; a controller located in the main body and comprising a controller memory, wherein the controller is configured to: receive locked state information and module identification information of the component module from the component module, wherein the locked state information indicates that the component module is in either a locked state or is in an unlocked state; determine that the component module is a registered component module when the module identification information is registered according to information in the controller memory; and characterized in that the controller is further configured to: identify the component module as accessible when the component module is in the locked state and the component module is the registered component module, or the component module is in the unlocked state; identify the component module as inaccessible when the component module is in the locked state and the component module is not the registered component module, connect to the component module and control functions of the component module when the component module is identified as accessible; change the locked state information from the unlock state into the locked state, and register the module identification information of the component module in the controller memory when a lock request is received; and change the locked state information from the lock state into the unlocked state, and delete the module identification information of the registered component module from the controller memory when an unlock request is received. a main body; a display; a component module coupled to the main body; a controller located in the main body and comprising a controller memory, wherein the controller is configured to: receive locked state information and module identification information of the component module from the component module, wherein the locked state information indicates that the component module is in either a locked state or is in an unlocked state; determine that the component module is a registered component module when the module identification information is registered according to information in the controller memory; receive locked state information and module identification information of the component module from the component module, wherein the locked state information indicates that the component module is in either a locked state or is in an unlocked state; determine that the component module is a registered component module when the module identification information is registered according to information in the controller memory; and characterized in that the controller is further configured to: identify the component module as accessible when the component module is in the locked state and the component module is the registered component module, or the component module is in the unlocked state; identify the component module as inaccessible when the component module is in the locked state and the component module is not the registered component module, connect to the component module and control functions of the component module when the component module is identified as accessible; change the locked state information from the unlock state into the locked state, and register the module identification information of the component module in the controller memory when a lock request is received; and change the locked state information from the lock state into the unlocked state, and delete the module identification information of the registered component module from the controller memory when an unlock request is received. identify the component module as accessible when the component module is in the locked state and the component module is the registered component module, or the component module is in the unlocked state; identify the component module as inaccessible when the component module is in the locked state and the component module is not the registered component module, connect to the component module and control functions of the component module when the component module is identified as accessible; change the locked state information from the unlock state into the locked state, and register the module identification information of the component module in the controller memory when a lock request is received; and change the locked state information from the lock state into the unlocked state, and delete the module identification information of the registered component module from the controller memory when an unlock request is received.