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:

Down Switch [Fw6 A EL, Fw6 Ax EL]
Purpose/Function The down switch detects the shift down operation of the selector lever. The down switch signal is sent to the TCM via CAN and is used for manual shift control and engine-transaxle integration control. Construction The down switch is installed to the se ...

Fuel Gauge Sender Unit Removal/Installation [2 Wd]
WARNING: Always keep sparks and flames away from fuel when servicing the fuel system. Fuel can be easily ignited which could cause serious injury or death, and damage to equipment. Fuel line spills and leakage from the pressurized fuel system are dangerous. Fuel can ignite a ...

Assist Handle Removal/Installation
Removal 1. Insert a tape-wrapped flathead screwdriver into the service hole and remove the assist handle covers. 2. Remove the assist handle in the direction of the arrow (1) and (2), while detach clips. NOTE: Remove the assist handle by shaking it up and down. Install ...