Improving the thermal efficiency of internal combustion engines over the engine operating range is essential for achieving optimum fuel economy. The thermal efficiency of the engine during cold start is one of the areas where significant improvement can be made if a suitable thermal management strategy is identified and implemented. Thermal management strategy in an engine can allow the engine to work at different operating temperatures in order to reduce the heat transfer loss by ensuring optimum volumetric efficiency, efficient combustion and adequate safety margin for the durability of mechanical components.The aim of the present work was to numerically model the warm-up characteristics of a 4 cylinder, 1.6 litre, turbocharged and intercooled, Euro IV, gasoline direct injected engine. It used a fully validated engine model which works based on the predictive combustion model. The engine model was then linked to coolant system model which includes engine block, cylinder head and a cooling circuit for the simulation of warm-up characteristics. This numerical model was developed using GT-Suite software and validated using the experimental data. The thermal management strategy employed by the ECU control strategy has been studied using this model.This paper presents the modelling strategies for heat transfer in engine block, cylinder head and cooling systems for the study of warm-up characteristics. It also presents the underlying assumptions, critical geometric parameters required for modelling warm-up characteristics and essential experimental data for developing a numerical model for the thermal management of a modern GDI engine.