GF07.61-P-3024MLK ME Oxygen Sensor Heater, Function

GF07.61-P-3024MLK ME Oxygen Sensor Heater, Function
- refinement package
- as of model year 09


Function requirements for oxygen sensor heater, general points
^ Circuit 87M ON (engine control ON)
^ Engine running
^ Coolant temperatures >20 °C
^ No high engine speeds

Oxygen sensor heater, general points
The oxygen sensor heaters bring the oxygen sensors (O2 sensors) up to operating temperature more rapidly. With controlled heating, they also prevent damage to the oxygen sensor ceramics.

To control the oxygen sensor heaters, the ME-SFI control unit (N3/10) reads the following sensors:
- Crankshaft position sensor (L5), motor speed
- Coolant temperature sensor (B11/4)

Oxygen sensor heater function sequence
Using a ground signal, the ME-SFI control unit actuates and synchronizes the oxygen sensor heaters of the LH and RH O2 sensors upstream of the CAT (G3/3, G3/4) and the LH and RH O2 sensors downstream of the CAT (G3/5, G3/6).

At coolant temperatures less than 20 °C and at high engine speeds, the oxygen sensor heaters are switched off to prevent damage (thermal shock).