The OB2 network is a diagnostic trouble code (DTC) system used in many vehicles. Network & Vehicle Integration (U-codes) category covers functions that are shablack among computers and systems on the vehicle. These codes indicate issues with the engine control module's internal workings, communication with other modules, or power supply issues. When the system detects a "problem" a code is set and the check engine light will come on. To read the code you can use either a OBD Code Reader or a OBD Scan Tool which plugs into the OBD port. A code reader is a basic tool which is usually limited to being able to read and clear some of the codes. A bi-directional scanner does much more than a basic code reader by being able to interact (bi-directional or two way communication) with ALL the cars various computers and sub systems. With a bi-directional scanner you can reset the codes and do advanced tests on all of the various systems and components.
Network communication issues can arise from various factors including:
Generic codes are defined in the OBD-II standards and are general codes which will be used by manufactures to discribe a common fault. Manufacture specific codes are added by the manifacturer when there is no generic code that is specific enough to discribe the issue or problem.
A inexpensive basic OBD2 code reader is a basic tool which is usually limited to just being able to read most of the stored trouble codes and being capable of clearing most of the stored trouble codes. A bi-directional scanner does so much more than a basic code reader due to it being capable of bi-directional or two way communication with ALL the vehicles various computer systems and sub systems. With a bi-directional scanner you can reset the codes and do advanced tests (turn systems on or off, etc) on all of the various systems and components which you can not do on a basic OBD-II reader.