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:

Refrigerant Pressure Sensor Inspection [Full Auto Air Conditioner]
1. Install the manifold gauge. 2. Verify the high-pressure side reading of the manifold gauge. 3. Measure the terminal voltage at PCM terminal 2BB, 2AX and 2AJ 4. Using the graph below, measure and verify the terminal voltages at 2AX. 5. Follow the PCM inspection when measuring the other te ...

DSC HU/CM Removal/Installation
WARNING: If the DSC HU/CM configuration is not completed, it could result in an unexpected accident due to the DSC being inoperative. If the DSC HU/CM is replaced, always use the automatic configuration function so that the DSC operation conditions are correct. If the DSC re ...

Rear Body Control Module (Rbcm)
Outline Positioned at the rear of the vehicle, the rear body control module (RBCM) performs numerous system controls for functions at the vehicle rear. Function The rear body control module (RBCM) controls the system based on the input/output signals. The functions ...