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:

Fuel System
Purpose, Outline A multiple hole type fuel injector has been adopted which provides higher fuel injection accuracy for improved fuel efficiency and output. Piston movement-compression by the 4-head cam inside the high pressure fuel pump heightens the fuel pressure, achieving imp ...

PCM Removal/Installation
CAUTION: There are two types of PCM settings. If the incorrect PCM is installed, it could cause interference with engine control. When replacing the PCM, verify the first four digits of the part number indicated on the PCM label before replacement, and replace the PCM with one ...

A/C Compressor Removal/Installation
1. Disconnect the negative battery cable.. 2. Discharge the refrigerant.. 3. Remove the front under cover No.2.. 4. Remove the drive belt.. 5. Disconnect the connector. 6. Remove bolts A. CAUTION: If moisture or foreign material enters the refrigeration cycle, cooling ability ...