An installation and maintenance method for maintaining a control module for remote starter and alarm system for vehicles includes the steps of plugging in a signal converter onto the control module, establishing an electronic connection between the control module and a first information processing device, obtaining a control information for the control module, and applying the control information on the control module. The signal converter includes a serial to wireless converter and the first information processing device includes a personal digital assistant (PDA). The method can further includes the steps of establishing a connection between the first information processing device and a second information processing device through a communication network and downloading an information from the second information processing device. A remote installation and maintenance system includes an information processing device, a communication network, and a server. The system installs and maintains the control module of the system.