Abstract: A maintenance alert device having a memory for storing information relating to the vehicle is disclosed. More specifically, a housing is provided for containing the components of the device, which include a processor for performing various functions programmed into the device, and a memory connected to the processor for storing information relating to the vehicle. This information may include, but is not limited to, maintenance history records and information relating to replacement parts of the customized vehicle systems. The device further includes a wiring harness for receiving signals from the vehicle, and a port for receiving information generated by the vehicle's odometer. The device also includes an input/output port for transferring information to and from the device. In operation, the maintenance alert device generates various maintenance signals after the occurrence of predetermined events monitored by the processor.