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:

Vacuum Pump Inspection
1. Pinch open the clamp using pliers and disconnect the vacuum hose from the vacuum pump.. 2. Install the vacuum gauge as shown in the figure, then check the vacuum. 3. Warn up the engine. If the pressure is less than the specification, inspect for the following. Malf ...

Center-Rear Position Seat Belt
Before using the center-rear lap/shoulder belt make sure tongue (A) and anchor buckle (B) are fastened. Fastening the Seat Belt 1. Grasp the seat belt tongue (C). 2. Slowly pull out the lap/shoulder belt. 3. Insert the seat belt tongue (C) into the seat belt buckle (D) until you hear a cli ...

After Service Precaution
WARNING: Fuel line spills and leakage are dangerous. Fuel can ignite and cause serious injuries or death and damage. When installing the fuel hose, perform “Fuel Leakage Inspection” described below. A person charged with static electricity could cause a fire or explosion, ...