In this paper we present a model for automotive system tests of functionality related to turn indicator lights. The model covers the complete functionality available in Mercedes Benz vehicles, comprising turn indication, varieties of emergency flashing, crash flashing, theft flashing and open/close flashing, as well as configuration-dependent variants. It is represented in UML2 and associated with a synchronous real-time systems semantics conforming to Harel’s original Statecharts interpretation. We describe the underlying methodological concepts of the tool used for automated model-based test generation, which was developed by Verified Systems International GmbH in cooperation with Daimler and the University of Bremen. A test suite is described as initial reference for future competing solutions. The model is made available in several file formats, so that it can be loaded into existing CASE tools or test generators. It has been originally developed and applied by Daimler for automatically deriving test cases, concrete test data and test procedures executing these test cases in Daimler’s hardware-in-the-loop system testing environment. In 2011 Daimler decided to allow publication of this model with the objective to serve as a ”real-world” benchmark supporting research of model based testing.