This professional OBD2 scanner reads and clears trouble codes as well as checks transmission temperature, brake pad, tire pressure, etc. In particular, they can save data and offer ECU programming. The third type includes professional OBD2 scanners, which are more sophisticated and richer in features than the two previous types. It has more features and provides you with more information, such as average speed, fuel usage, and what is going on in your vehicle right now. Basic code readers can be both wireless and corded. It uses diagnostic trouble codes to notify you about the issue and then clears the codes if needed. The first type is the most common and affordable option. What is the best OBD2 scanner? There are three types of these devices: a basic code reader, a DIY scanner, and a professional scanner.