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:

Air Intake Actuator Inspection [Full Auto Air Conditioner]
1. Connect battery positive voltage to air intake actuator terminal B (or C), connect terminal C (or B) to ground, and then verify that the air intake actuator operates as shown in the table. If the operation condition is not normal, replace the air intake actuator. ...

Hazardous Driving
WARNING Be extremely careful if it is necessary to downshift on slippery surfaces: Downshifting into lower gear while driving on slippery surfaces is dangerous. The sudden change in tire speed could cause the tires to skid. This could lead to loss of vehicle control and an accident. When driv ...

Clutch Fluid Leakage Inspection [C66 M R]
CAUTION: Do not allow clutch fluid to get on a painted surface. Clutch fluid contains properties which can dissolve the paint. If clutch fluid gets on a painted surface, wash it off with water immediately and wipe the area off completely. 1. Verify reserve tank cap is on tight. ...