What is ESN PIN Code ESN PIN code is a 6-digit code for Eclipse navigation units in Japanese origin cars. This application could be used to generate a 6-digit unlock PIN when entered into the car multimedia device at ESN Pin screen, could unlock various features of the Car Audio Unit. To generate an ESN password, an ESN serial number is required. Reason for ESN Unlocking ESN is a safety system that causes the navigation and sound functions to become inoperative when the battery terminal is