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:

Tire Pressure Monitoring System Set Switch Inspection
1. Remove the TPMS set switch.. 2. Verify that the resistance between the TPMS set switch terminals B and C is as indicated in the table. If not as indicated in the table, replace the TPMS set switch. TPMS set switch specification Terminal ...

Side Step Molding Removal/Installation
1. Set the rear over fender aside.. 2. Insert a tape-wrapped flathead screwdriver shown in the figure and remove the clip A in the direction of arrow (1). 3. Slide the side step molding in the direction of the arrow (2) shown in the figure and remove clips B from side step molding. 4. ...

Front Door Speaker Inspection
1. Disconnect the negative battery cable.. 2. Remove the following parts: a. Inner garnish. b. Front door trim. 3. Disconnect the front door speaker connector.. 4. Verify that the resistance and continuity between the front door speaker terminals is as indicated in the table. ...