Engine Codes Engine Codes Engine Codes, Being Able To Read Them Can Be A Valuable Tool. With today’s unlimited number of sensors and computers having a code reader is a must for anyone willing to tackle their own repairs. Until recently, an OBD-II code reader tool code reader was not typically found in the do-it-yourselfers tool box. For working on 1996 & newer vehicles, however, it can be really useful. An OBD-II code reader is an electronic device that allows you to plug into your computer’s OBD diagnostic port and access technical information. Search Our Site or Choose Your Topic Below ! Honda 95 & Earlier OBD1 Trouble Code Info Variable valve timing (VVT) Generic OBD II Fault Codes What can cause your check engine light to come on? Stay tuned for more updates on: Engine Codes.