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:

Brake/Clutch Fluid
Inspecting Brake/Clutch Fluid Level The brakes and clutch draw fluid from the same reservoir. Inspect the fluid level in the reservoir regularly. It should be kept at MAX. The level normally drops with accumulated distance, a condition associated with wear of brake and clutch linings. If it is ...

Floor Side Panel Removal [Panel Replacement]
Symbol Mark Removal Procedure 1. Drill the 35 locations indicated by (A) shown in the figure, then remove the floor side panel No.1. 2. Drill the 5 locations indicated by (B) shown in the figure. 3. Drill the 4 locations indicated by (C) from rear wheel housing shown in the figure. ...

Neutral Switch Inspection
Continuity Inspection 1. Disconnect the negative battery cable.. 2. Remove the neutral switch.. 3. Inspect for continuity between neutral switch No.1 terminal A and B. If not as specified, replace the neutral switch No.1.. Specification Measured conditio ...