Mazda CX-5 Service & Repair Manual: Heated Oxygen Sensor (HO2 S) Heater Control [Skyactiv G 2.0]

Mazda CX-5 Service & Repair Manual / HVAC / General / Heated Oxygen Sensor (HO2 S) Heater Control [Skyactiv G 2.0]

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

Operation

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


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%	HO2S not activated
0?100% (Determined by engine speed and charging efficiency)	Other than the above

Front Heat Duct Removal/Installation

1. Disconnect the negative battery cable.. 2. Remove the following parts: a. Dashboard under cover. b. Side wall. c. Glove compartment. 3. Detach the tab and remove the front heat duct. LH ...

Heater Core

Purpose The heater core heats passing air. Function A portion of the engine coolant is taken into the heater core to heat the air passing through the heater core. Co ...

Other materials:

Turbine/Input Shaft Speed Sensor, Output Shaft Speed Sensor [Fw6 A EL, Fw6 Ax EL]
Purpose/Function The turbine/input shaft speed sensor detects the rotation speed of the input shaft (low clutch drum). The output shaft speed sensor detects the rotation speed of the output shaft (primary gear). The turbine/input shaft speed sensor and output shaft speed ...

Front Center Speaker Inspection
1. Disconnect the negative battery cable.. 2. Remove the center speaker grille.. 3. Remove the front center speaker.. 4. Verify that the resistance between the front center speaker terminals is as indicated in the table. If not as indicated in the table, replace the front center ...

Coupler Component Removal/Installation [Fw6 A EL, Fw6 Ax EL]
WARNING: A hot transaxle and ATF can cause severe burns. Turn off the engine and wait until they are cool. Always wear protective eye wear when using the air compressor. If the air compressor is used, any particles of dirt or soiling could spatter and get into the eyes. ...