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:

Engine Coolant Temperature (ECT) Sensor Inspection
Resistance Inspection WARNING: When the engine is hot, it can badly burn. Turn off the engine and wait until it is cool before removing the ECT sensor. ECT Sensor No.1 1. Remove the ECT sensor No.1.. 2. Place the ECT sensor No.1 in water with a thermometer, and heat the water ...

Evaporative Emission (Evap) Control System
Purpose, Outline Prevents release of evaporative gas into the atmosphere. The intake manifold vacuum introduces evaporative gas to the intake manifold via the charcoal canister and the purge solenoid valve. System Diagram U.S.A. and CANADA Except U.S.A. and CANADA ...

Blind Spot Monitoring (Bsm) Control Module Inspection
1. Disconnect the negative battery cable.. 2. Remove the rear combination light.. 3. Remove the rear bumper.. 4. Connect the negative battery cable.. 5. Verify that the voltages of each of the terminals are as indicated in the terminal voltage table (reference). If the voltage is n ...