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:

Blind Spot Monitoring (Bsm) Off Indicator Light
Purpose The BSM OFF indicator light informs the driver that the Blind Spot Monitoring (BSM) system is turned off or there is a malfunction in the system. Function The instrument cluster illuminates the BSM OFF indicator light based on the BSM system off signal sent via a CA ...

Parking Brake Lever Inspection
Stroke Inspection 1. Pump the brake pedal a few times. 2. Pull the parking brake lever two to three times. 3. Inspect the parking brake stroke by slowly pulling at point A 50 mm {2.0 in} from the end of the parking brake lever with a force of 98 N {10 kgf, 22 lbf} and counting the number of ...

Power Steering Malfunction Indicator Light
Purpose The power steering malfunction indicator light warns the driver that there is a malfunction with the electric power steering (EPS) system. Function If there is a malfunction in the EPS system, the power steering malfunction indicator light illuminates. If th ...