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:

Electric Variable Valve Timing Motor/Driver Inspection
WARNING: A hot engine can cause severe burns. Turn off the engine and wait until it is cool before servicing. CAUTION: Do not disassemble the electric variable valve timing motor/driver because it is a precision unit. Do not apply excessive force when rotating the ...

Coolant Reserve Tank Removal/Installation
1. Remove in the order indicated in the table. 2. Install in the reverse order of removal. 1 Wiring harness 2 Hose 3 Coolant reserve tank (See Coolant Reserve Tank Removal Note.) Coolant Reserve Ta ...

Lights On Reminder Warning Alarm
Purpose The lights-on reminder warning alarm notifies the driver that the TNS and headlights are not turned off. Function The instrument cluster receives the following vehicle condition signals via the CAN signal from the start stop unit and rear body control module (RBCM). ...