HEATED OXYGEN SENSOR (HO2S) HEATER CONTROL [SKYACTIV-G 1.3, SKYACTIV-G 1.5]


id0140q1785600


Outline

•  Based on the control of the HO2S heater, a stabilized oxygen concentration is detected (even at low exhaust temperatures), and feedback control of fuel injection (even at cold engine start) is made possible for improved cold temperature exhaust emission performance.
•  Both emission performance and sensor protection have been improved by duty control of the heater (according to engine operation conditions (exhaust gas temperature)).

Block Diagram

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Operation

•  The PCM operates the HO2S heater based on the following control conditions.

PCM (200 pin type)

Output duty ratio

Control condition

0%
•  Engine stopped
•  Fuel cut injection control is in engine start zone
•  Engine coolant temperature is −10 °C {14 °F} or less
•  Other than battery voltage of 10—16 V
•  Within a fixed period of time after engine start (varies according to engine coolant temperature)
30―50%
•  HO2S not activated
30―70%
•  When engine is stop by i-stop control
0―100%
(Determined by engine speed and charging efficiency)
•  Other than the above

PCM (186 pin type)

Output duty ratio

Control condition

0%
•  Engine stopped (excludes engine stop by i-stop control)
•  Fuel cut injection control is in engine start zone
•  Engine coolant temperature is −10 °C {14 °F} or less
•  Other than battery voltage of 9—16 V
•  Within a fixed period of time after engine start (varies according to engine coolant temperature)
0―100%
(Duty ratio determined by measuring the element temperature by the HO2S sensor heater elementimpedance)
•  After engine warm-up (value fluctuates by battery condition, etc.)