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 Pump Unit
Purpose, Function Supplies fuel in the fuel tank to the high pressure fuel pump. Based on the control signal from the PCM, the fuel pump operates by the operation of the fuel pump relay and the fuel pump control module. Construction 2WD The fuel pump unit is installed ...

Shift Solenoid No.2 [Fw6 A EL, Fw6 Ax EL]
Purpose/Function Shift solenoid No.2 adjusts the hydraulic pressure in the 2-6 brake circuit based on the current demand from the TCM according to the vehicle conditions. Construction Shift solenoid No.2 is installed to the solenoid control valve body. Shift solenoid N ...

Relay And Fuse Block Disassembly/Assembly
1. Insert a tape-wrapped flathead screwdriver into the service hole in the position shown in the figure. 2. Move the flathead screwdriver in the direction of the arrow (1) shown in the figure, pull up relay and fuse block No.1 in the direction of the arrow (2) shown in the figure, and de ...