Mazda CX-5 Service & Repair Manual: Heated Oxygen Sensor (HO2 S) Heater Control [Skyactiv G 2.0]

Mazda CX-5 Service & Repair Manual / HVAC / General / Heated Oxygen Sensor (HO2 S) Heater Control [Skyactiv G 2.0]

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

Front Heat Duct Removal/Installation

1. Disconnect the negative battery cable.. 2. Remove the following parts: a. Dashboard under cover. b. Side wall. c. Glove compartment. 3. Detach the tab and remove the front heat duct. LH ...

Heater Core

Purpose The heater core heats passing air. Function A portion of the engine coolant is taken into the heater core to heat the air passing through the heater core. Co ...

Other materials:

Tire Pressure Warning Alarm
Purpose The tire pressure warning alarm warns the user that a tire pressure has decreased or notifies the user that the tire pressure warning alarm has been reset. Function If the instrument cluster receives a tire pressure warning alarm request signal sent from the D ...

Differential Oil Temperature Sensor Inspection
WARNING: Hot differential oil may cause severe burns. Do not perform maintenance while differential oil is hot. 1. Disconnect the negative battery cable. 2. Disconnect the differential oil temperature sensor connector and remove the differential oil temperature sensor. 3. Wrap ...

Accelerator Pedal Position (App) Sensor Inspection
Voltage Inspection NOTE: Because the APP sensor is integrated in the accelerator pedal, replacing the APP sensor includes replacement of the accelerator pedal. 1. Connect the M-MDS to the DLC?2. 2. Switch the ignition ON (engine off or on). 3. Verify that the APP sensor output ...