ISO 22900-3:2012侧重于面向对象编程接口的描述。目标是实现服务器应用程序的能力，这些应用程序在车辆通信系统的设计、生产和维护阶段使用，相互兼容，因此是可交换的。从用户的角度来看，车载控制单元的访问和集成由相应的应用程序、通信服务器和用于诊断的VCI模块提供。用户有权访问诊断服务车辆中的控制单元（ECU）。

ISO 22900-3:2012 focuses on the description of an object-oriented programming interface. The objective is the ability to implement server applications, used during the design, production and maintenance phase of a vehicle communication system, compatible to each other and thus exchangeable. From a user's perspective, access and integration of on-board control units is provided by a corresponding application, the communication server and a VCI module for diagnostics. The user is granted access for the handling of control units (ECUs) in vehicles for the diagnostic services.