The present invention relates to a method and a system for testing control software of a controlled system, the controlled system comprising one or more electronic control units, one or more actuators, and one or more sensors, each sensor being adapted to input a respective sensor signal to at least one of the one or more electronic control units and each actuator being adapted to act responsive to respective control signals input from at least one of the electronic control units, and each electronic control unit being configured to execute a respective executable control program based on control software code data to output one or more control signals to the one or more actuators on the basis of input sensor signals. The control testing process comprises providing control software code data for each of the one or more electronic control units, providing simulation code data for the controlled system, creating a system model based on the provided control software code data provided for each of the one or more electronic control units and the provided simulation code data, creating an executable program based on the created system model, and performing a software verification process on the basis of the executable program.