End of line test (EOL) of Engine Control Units (ECU) is the process of ECU functions validation before releasing ECUs to the car assembly process. Examples of ECU function that need to be validated are idle control, air path control and faults manager function. To perform EOL, a vehicle and a chassis dynamometer are used to enable control functions validation inside the ECU. However, this poses high operating cost and long setup time.This paper presents the development of Hardware-in-the-Loop (HiL) system, which imitates real vehicle behavior on a chassis dynamometer. The diesel high pressure pump model was developed using an empirical dynamic modeling approach. The engine model was developed using AVL BOOST RT software, an engine cycle simulation modeling approach. The vehicle model was developed using AVL CRUISE software. In order to interface the engine and vehicle models with the ECU, HiL system was implemented.In the new EOL process, the vehicle was operated following the Extra Urban Driving Cycle (EUDC) including short engine idling time. During the test, the control and safety functions check were performed. Agreement of the test results from HiL system and the chassis dynamometer test-bed showed that the developed platform on HiL could be perfectly utilized for EOL test.