The engine compartment of passenger car application contain various source which radiates the produced heat and raises the temperature level of the compartment. The rise in compartment temperature increases the individual component body temperature. The rise in body temperature of critical components can endanger the life or functionality of the specific component or a system in which it operates. The aim of this paper is to strategise thermal protection of the rear mounted engine and it's components of a vehicle having radiator and cooling fan mounted in front. An additional ventilation fan with speed sensor is fitted alongside rear mounted engine and a unique monitoring technique framed in the EMS ECU to protect critical components like HT cables, alternators, ECU, wiring harness etc. from thermal damage. The EMS continuously monitors the engine speed, vehicle speed and the PWM signal of ventilation fan to ensure the intended operation of the ventilation fan. With the implementation of additional ventilation fan it is observed that maximum engine compartment temperature do not exceed safe operating temperature limit when the vehicle is driven in all road load condition (including highway, city & gradient drive conditions) and in all vehicle operating conditions. Excessive operation at higher compartment temperature unnecessarily causes individual component life & performance to deteriorate at considerably faster rate. Thus, method of the present disclosure ensures that every component in engine compartment is operating in safe operating limits. In-case any failure occurs in the ventilation fan, EMS diagnosis strategy identify fault and indicates the problem to the driver through tell-tail. EMS also restricts the vehicle speed to safely maneuver vehicle to the nearest service center for repair.