Thermal comfort is increasingly recognized as a vital component of the in-vehicle user experience, influencing both occupant satisfaction and perceived vehicle quality. At the core of this functionality is the Climate Control Module (CCM), a dedicated embedded Electronic Control Unit (ECU) within automotive HVAC system [6]. The CCM orchestrates temperature regulation, airflow distribution, and dynamic environmental adaptation based on sensor inputs and user preferences.
This paper introduces a comprehensive Hardware-in-the-Loop (HIL) [3] testing framework to validate CCM performance under realistic and repeatable conditions. The framework eliminates the dependencies on physical input devices—such as the Climate Control Head (CCH) and Infotainment Head Unit (HU)—by implementing virtual interfaces using real-time controller, and Dynamic System modelling framework for plant models. These virtual components replicate the behaviour of physical systems, enabling closed loop testing with high fidelity.
Sensor data simulate critical environmental parameters including solar radiation load, outside air temperature (OAT), and evaporator temperature etc. Actuator of HVAC components such as blower motors, air flap actuators, and compressor control systems are used to represent real loads. The HIL setup supports real-time signal simulation, protocol emulation over LIN and CAN networks, and automated test execution. Additionally, fault injection capabilities allow for robust validation of diagnostic strategies and safety mechanisms.
The framework facilitates early-stage validation, accelerates development cycles, and enhances product maturity by enabling exhaustive scenario testing without reliance on physical prototypes. Key outcomes include improved test coverage, reduced time-to-market, and scalable integration for future vehicle platforms. The paper also outlines future directions, including the incorporation of thermal intelligence through AI/ML algorithms, and the deployment of remote or cloud-based testing environments to support distributed development teams.