Mazda CX-5 Service & Repair Manual: Air Fuel Ratio (A/F) Sensor Heater Control [Skyactiv G 2.0]

Mazda CX-5 Service & Repair Manual / HVAC / General / Air Fuel Ratio (A/F) Sensor Heater Control [Skyactiv G 2.0]

Outline

Based on the control of the A/F sensor 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).
A pre-heater has been adopted to prevent water, produced from the exhaust system when the engine is started, from adhering to the sensor and damaging it.

Block Diagram

Operation

Pre-heater control

The A/F sensor heater is operated at a duty ratio of approx. 15% within the specified time directly after the engine is started.

Normal control

The PCM operates the A/F sensor based on the following control conditions:


Output duty ratio	Control condition
0%	Ignition switched off Engine stopped Engine start (cranking)
0?100% (Duty ratio determined by measuring the element temperature by the A/F sensor heater element impedance)	After engine warm-up (value fluctuates by battery condition, etc.)

Output duty ratio

Control condition

Ignition switched off
Engine stopped
Engine start (cranking)

0?100%

(Duty ratio determined by measuring the element temperature by the A/F sensor heater element impedance)

After engine warm-up (value fluctuates by battery condition, etc.)

Air Filter Removal/Installation

1. Remove the glove compartment.. 2. Remove the air filter. 3. Install in the reverse order of removal. ...

Airflow Mode Main Link Removal/Installation

Full-auto Air Conditioner 1. The airflow mode main link is installed to the airflow mode actuator. When removing the airflow mode main link, refer to the airflow mode actuator removal/installation. ...

Other materials:

Engine Oil Pressure Warning Light
Purpose The engine oil pressure warning light warns the driver that the engine oil level is insufficient. Function When the instrument cluster receives the engine oil pressure warning light request signal sent from the PCM via the CAN signal, it illuminates the engine oi ...

Shroud Panel Removal/Installation
CAUTION: Since the servicing is performed with the hood open, secure the hood using a piece of wood to prevent it from falling. 1. Disconnect the negative battery cable.. 2. Remove the following parts: a. Seal board upper. b. Front bumper. c. Front combination light. d. Sh ...

Front Wiring Harness Protector Removal/Installation
Front Wiring Harness Protector No.1 1. Disconnect the negative battery cable.. 2. Remove the air cleaner case.. 3. While pressing the tabs of clip A in the direction of the arrows (1) shown in the figure, pull clip A in the direction of the arrow (2) shown in the figure to detach the tab of ...