E 320 Coupe (124.052) L6-3.2L (104.992) (1994)
Oxygen Sensor Voltage
A rich mixture will produce a high voltage (up to 1.0V) and a lean mixture will produce a lower voltage.
Oxygen Sensor Heater Signal
PURPOSE
To keep the oxygen sensors (G3/1 and G3/2) at a consistant operating temperature (approx. 600 °C / 1112 °F), the HFM-SFI control module
controls the oxygen sensor heating element. (Either directly or through the relay module (K35) depending on model. Refer to wiring diagram.)
OPERATION
When the engine is started, the oxygen sensor heating element is in operation. If the engine exceeds 5500 RPM, the heating element is turned off.
Operation restarts when the engine speed drops below 5000 RPM.
GF07.04-P-4103-01F O2 Sensors Function
GF07.04-P-4103-01F O2 Sensors Function
The sensor ceramic is conductive for oxygen ions from approx. 300 degrees C. If the oxygen share varies greatly on both sides of the ceramic probe
body, a voltage (Nernst concentration cell) is generated on the friction planes by means of the particular properties of the ceramic probe body on the
friction plane. This is a measure for the residual oxygen content in the exhaust.