SLK 320 (170.465) V6-3.2L (112.947) (2002)
- Front SAM control unit with fuse and relay module Model 203, 209, 211
The current in the cold state is increased by approximately 4 times. At coolant temperatures below approx. 20 °C and at high engine speeds, the sensor
heater is switched off.
Engine 112, 113
The sensor heaters for the left and right O2 sensors are connected in parallel in the ME-SFI control unit.
Engine 119
The sensor heaters for the left and right O2 sensors are connected in parallel.
Engine 120
The sensor heaters for the left and right O2 sensors are assigned to the respective engine control unit.
Engine 137
Each sensor heater has its own, short-circuit proof output stage in the engine control unit with diagnosis. As a protection for the ceramic, the sensor
temperature upstream of TWC is limited to approx. 350 °C in the condensation phase after cold start. After this, the temperature is controlled to approx.
700 °C. An exhaust temperature is determined from various engine operating data for this purpose and the sensor heated accordingly.
Different values apply to the O2 sensor heaters downstream of TWC.
ME-SFI Two-Sensor Control Function
ME-SFI Two-sensor Control Function