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:

Warning Sound is Activated
Lights-On Reminder If lights are on and the ignition is switched to ACC or the ignition is switched off, a continuous beep sound will be heard when the driver's door is opened. NOTE • When the ignition is switched to ACC, the “Ignition Not Switched Off (STOP) Warning Beep” ove ...

Energy Absorbing Form Removal/Installation
1. Disconnect the negative battery cable.. 2. Remove the seal board upper.. 3. Remove the front bumper.. 4. Insert the flathead screwdriver shown in the figure, push fasteners A for back side of front bumper reinforcement arrow shown in the figure. 5. Pull the energy-absorbing form in ...

A/C Unit Disassembly/Assembly
1. Disassemble in the order indicated in the table. CAUTION: If a non-specified grease is used, it may result in abnormal noise or improper operation of the links. Apply only the specified grease to each link. 2. Assemble in the reverse order of disassembly. ...