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:

Clock Spring Removal/Installation [Standard Deployment Control System]
CAUTION: If the disc on the combination switch is deformed or has foreign material adhering to it, performance of the steering angle sensor may be reduced, causing abnormal operation. When handling the clock spring, be careful not to deform the disc and make sure there is no foreign ...

Throttle Body Inspection
Resistance Inspection 1. Disconnect the negative battery cable.. 2. Disconnect the throttle body connector. 3. Measure the resistance between throttle body terminals E and F. Throttle body resistance 1.38 ohms [20°C {68 °F}] If not as specified, replace the throttle ...

Sunvisor Removal/Installation
1. Disconnect the negative battery cable. (with vanity mirror illumination). 2. Remove the screw A. 3. Rotate the sunvisor in the direction of the arrow. 4. Unhook and remove the sunvisor. 5. Disconnect the vanity mirror illumination connector. (with vanity mirror illumination) 6. Pr ...