Mazda CX-5 Service & Repair Manual: Heated Oxygen Sensor (HO2 S) Heater Control

Mazda CX-5 Service & Repair Manual / Engine / Control / Heated Oxygen Sensor (HO2 S) Heater Control

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

Engine Coolant Temperature (ECT) Sensor

Purpose/Function Detects the ECT as basic information for mainly determining the fuel injection amount. Detects the ECT and inputs it to the PCM as an ECT signal. The ECT sen ...

Heated Oxygen Sensor (HO2 S) Inspection

HO2S Inspection 1. Connect the M-MDS to the DLC?2. 2. Switch the ignition ON (engine on). 3. Warm up the engine to normal operating temperature. 4. Access the following PIDs using the M-MDS.. ...

Other materials:

Electric Variable Valve Timing Relay [Skyactiv G 2.0]
Purpose, Function The electric variable valve timing actuator relay supplies power to the electric variable valve timing motor/driver after receiving the signal from the PCM. Construction The electric variable valve timing actuator relay is installed to the relay block.. ...

Procedure [Plastic Body Parts]
Repair of polypropylene bumpers having damage that has reached the surface of the polypropylene and are too serious to be restored by painting only. 1. Cut the rough edges around the damage with a knife to make it smooth. Sand the area with a sander to make an angle of about 45°. 2. ...

Audio Unit Personalization Features Setting Procedure
Door Locks Systems 1. Switch the ignition ON (engine off or on). 2. Turn the audio unit power on. 3. Select the following from the audio unit screen. a. “Setup” b. “Vehicle” c. “Door Locks“ 4. Select the following items and change the setting. Advanced keyless entry system ...