ERC codes for car media player that has lock due to dead battery, malfunction or removal of unit. We use software to generate the code needed to unlock your media player. Your 16 digits serial number will be used to generate the 8 digit code needed to unlock your unit. Instruction to obtain serial number is as followed 1. press an hold main button on unit. 2. turn parking lights on for 3-4 times until new screen appears. 3.press an hold active button an you will get 16 digits serial number, if it has not work check online for other procedures. Supported units are ND, NH,NS,NM,W japanese car DVD Navigation Head Units.