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O2 sensor heater, function - GF07.61-P-3025AM

ENGINE 113.990 in MODELS 211, 219 

ENGINE 113.991 in MODELS 215, 220 

ENGINE 113.992 in MODEL 230 

ENGINE 113.993 in MODEL 463 

ENGINE 113.995 in MODEL 230 

Fig 1: O2 Sensor Heater Function Diagram
G04839918

The purpose of the O2 sensor heater is to rapidly heat up the O2 sensors to their operating temperature while preventing damage to the sensor ceramic through the relevant heat control.

The O2 sensor heater is actuated and pulsed by the ME control unit via a ground signal.

The voltage supply for the O2 sensor heaters is provided via the ME control unit by the relevant fuse and relay module or SAM.

The sensor heater is switched off at coolant temperatures below approx. 20°C and at high engine speeds as a protection for the sensor ceramic.

IMPORTANT The power absorption capacity of the O2 sensor heater from an exhaust gas temperature of 350°C is less than 7 W.

The current in the cold state is increased by the factor 4.

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