Component description for the coolant thermostat - GF20.10-P-3162CY

ENGINE 272.911 in MODEL 204.0 up to Model Year 8

ENGINE 272.921 in MODEL 204.0/2 up to Model Year 8

ENGINE 272.947 in MODEL 204.0/2 up to Model Year 8

ENGINE 272.948 in MODEL 204.0 up to Model Year 8

ENGINE 272.961 in MODEL 204.0/2 up to Model Year 8

ENGINE 272.971 in MODEL 204.0 up to Model Year 8

Location

Fig 1: Identifying Coolant Thermostat

Courtesy of MERCEDES-BENZ USA

The coolant thermostat is located at the front on the timing case cover.

Task

For thermal management, the coolant thermostat regulates the coolant temperature in the range of about 80 to 100°C.

Above around 110°C, the coolant thermostat is always fully opened independently of actuation (limp-home function).

Function

There is a heating element and a three-disk thermostat in the coolant thermostat.

Actuation of the heating element takes place at the ground end by the ME-SFI [ME] control unit (N3/10). The voltage supply takes place from "circuit 87 M".

Through heating the three-disk thermostat, it opens the coolant circuit for the engine radiator. The opening cross-section for the three-disk thermostat is regulated via the duty cycle.

Three-disk thermostat (schematic)

Fig 2: Identifying Three-Disk Thermostat Function Schematic

Courtesy of MERCEDES-BENZ USA