C 300 (204.054) V6-3.0L (272.947) (2008)
Sensor heating
In order to bring ceramic probe bodies quickly up to operating temperature the voltage-jump oxygen sensors are heated constantly with a heat output of
about 7 W.
The sensor heaters are actuated by the ME-SFI [ME] control unit by means of a ground signal. The heater current in the cold state is increased
approximately by a factor of 4.
At coolant temperatures greater than about 20 °C and at high engine speeds, sensor heaters are switched off to prevent overheating (thermal shock).