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:

Seat Track Position Sensor Removal/Installation [Two Step Deployment Control System]
1. Switch the ignition to off. 2. Disconnect the negative battery cable and wait for 1min or more.. 3. Remove the front driver’s seat.. 4. Disconnect the connector from the seat track position sensor by pressing the connector tab and pulling out the lock lever in the direction of the arro ...

Air Bag System Warning Light [Two Step Deployment Control System]
Purpose The air bag system warning light notifies the driver of a malfunction in the SRS air bag system. Function If a malfunction occurs in the SRS air bag system, the air bag system warning light illuminates or flashes. Construction LEDs (light-emitting d ...

Crankshaft Position (CKP) Sensor
Purpose/Function Detects the crankshaft speed as basic information for mainly determining the fuel injection timing and ignition timing. Detects the crankshaft speed and inputs it to the PCM as a CKP signal. Construction Installed on the side of the cylinder block (ri ...