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:

Rear Mount Camera Removal/Installation
CAUTION: The audio unit communicates with the rear mount camera and records the presence/non-presence of the rear mount camera when the ignition is switched to ACC or ON (engine off or on) after connecting the negative battery cable. If the commander switch is installed wit ...

Front Over Fender Removal/Installation
1. Remove fastener A. 2. Pull the front over fender lower in the direction of the arrow (1) while removing hook B and pin C. 3. Remove fasteners D. 4. Pull the front over fender upper in the direction of the arrow (2) while removing clips E. 5. Install in the reverse order of ...

Room Straight Line Dimensions (1) [Dimensions]
Point symbol Designation Hole diameter or bolt or nut size mm {in} A Front pillar inner datum hole ?7 {0.3} B Front pillar inner datum hole ?7 {0.3} C ...