A special candle is screwed into the combustion chamber of each of the cylinders, consisting of a body with a heating rod pressed into it, formed by two spirals: heating and adjusting. After applying voltage, the heating coil in the rod heats up within a few seconds to a temperature of + 850°C, while the current through the candle reaches 30A. With an increase in the degree of heating, the resistance of the spiral also increases, which helps to reduce the current strength to a value of 15 - 25 A. After turning off the warning lamp of the incandescent system on the instrument panel, the engine can be started.
The time taken to preheat the cylinders is no more than 10 seconds and is regulated by a special relay and an engine control module (ECM), via coolant temperature sensor (ECT) receiving information about the current temperature of the engine. Based on the analysis of the received data, the ECM controls the duration of the heating system and the operating current of the heating.
Note. On diesel engines with direct injection, the need for pre-glow occurs only at temperatures below 0°C.