In model-driven development, the correctness of models is essential. Testing as soon as possible reduces the cost of the verification and validation process. Considering separately PIM and PSM reduces the test complexity and helps the evolution of the system model. In order to test models before their final implementation, we propose an approach to guide the tester through the process of designing tests at the model level. We target model testing for Service-based Component Models. The approach produces test harness and provides information on how to bind the services of the components under test and how to insert the relevant data. The tests are then executed by plunging the harness into a technical platform.