Before the widespread adoption of the UDS protocol, understanding live data from European vehicles, particularly Volkswagen/Audi (VW/Audi), required familiarity with Messwerteblock (MWB). MWB represents groups of parameter identifiers, offering insights into various vehicle systems. These groups are consistently referenced in service manuals across different VW/Audi models.
For instance, MWB 0-9 typically displays general engine data like RPM, temperature, and load. MWB 10-19 focuses on ignition and misfire data, including misfire counters and knock retard. MWB 30-39 delves into fuel trims and air/fuel ratio information. Other groups like MWB 90-99 (VVT) and MWB 120-129 (CAN communication) provide specific system insights.
This structured approach to data presentation mirrors strategies employed by other manufacturers like General Motors (GM), which categorize data into fuel trim, misfire, and VVT, among others.
Certain scan tools excel at interpreting this data. ROSS-TECH VCDS, for example, deciphers and explains MWB data clearly for users. However, some tools, including certain Autel and Launch models, present the data in a less organized manner, requiring consultation with service information (SI) for deeper understanding.
With the advent of UDS protocol in newer controllers, data selection becomes more straightforward. Similar to using an Autel scan tool on a Chrysler or Ford, users can select desired parameters from a PID list. This standardized approach simplifies data access across different vehicle makes.
While other European manufacturers may employ different data organization methods, understanding their underlying logic is crucial. Thorough research and access to comprehensive service information are often key to unlocking the insights hidden within diagnostic data. Sometimes, the challenge lies not in the complexity of the data itself, but in the availability of clear and comprehensive documentation.
