SEBU8726-03 47 Operation Section Sensors and Electrical Components Engine Option or Parts that are Supplied Loose Illustration 37 g02821639 Typical example (20) Glow plug control unit (21) Inlet air temperature sensor (22) Breather heater Some engines can have a breather heater (22) for the crankcase breather installed. i05325624 Sensors and Electrical Components (Aftertreatment) There are two types of aftertreatment that can be installed. The engine power will determine the type of aftertreatment that is installed.