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:

General Procedures (Brake)
Wheel and Tire Installation 1. When installing the wheels and tires, tighten the wheel nuts in a criss-cross pattern to the following tightening torque. Tightening torque 108—147 N·m {12—14 Kgf·m, 80—108 ft·lbf} Brake Lines Disconnection 1. If any brake line has been ...

Camshaft Position (CMP) Sensor Inspection
Intake CMP Sensor Visual inspection CAUTION: When replacing the CMP sensor, make sure there is no foreign material on it such as metal shavings. If it is installed with foreign material, the sensor output signal will malfunction resulting from fluctuation in magnetic flux and caus ...

Control System [Full Auto Air Conditioner]
Outline Refrigerant pressure sensor adopted in which refrigerant pressure is changed into a linear electric signal and precise information is transmitted. MS-CAN for communication between the instrument cluster and climate control unit adopted. Climate control un ...