Toyota Camry Hybrid AHV40 Manual page 230

EG-42
2) Construction
D The basic construction of the heated oxygen sensor and the air-fuel ratio sensor is the same. However,
they are divided into the cup type and the planar type, according to the different types of heater
construction that are used.
D The cup type sensor contains a sensor element that surrounds a heater.
D The planar type sensor uses alumina, which excels in heat conductivity and insulation, to integrate a
sensor element with a heater, thus improving the warm-up performance of the sensor.
Dilation Layer
Platinum
Electrodes
Planar Type Air Fuel Ratio Sensor
ENGINE - 2AZ-FXE ENGINE
Alumina
Atmospheric
Alumina
Heater
Sensor Element (Zirconia)
Platinum Heater
Electrodes
Sensor Element
(Zirconia)
Cup Type Heated Oxygen Sensor
Atmospheric
271EG45