Not sure it works for Nissan/ Infiniti , but do you still have the old ECU, and did it communicate with the Maxi Sys Pro? If so reinstall the old ECU, Enter Manual diagnosis, select System Selection, and see if it communicates and does an auto scan, record the codes and do a quick erase. If so exit diagnosis and then go to Service or Hot Function menu and see if it offers a selection for replace ECU or programmable module installation. Follow the instructions, It pulls information out of the old ECU and then prompts you when to install the new ECU. It should read the VIN # and write it to the new module , then ask you if it is correct or not and may give you the option to enter or edit a VIN number.