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:

Rear Scuff Plate Removal/Installation
1. Take the shaded area shown in the figure, detach tab A while pulling the rear scuff plate in the direction of the arrow (1) shown in the figure, then detach hook B, clips C, pins D while pulling in the direction of the arrow (2). 2. Take the shaded area shown in the figure, detach tab E whi ...

Clutch Pedal Position (CPP) Switch [Skyactiv G 2.0]
Purpose/Function Detects the connection status of the clutch. Construction Installed on the clutch pedal. An ON/OFF type switch has been adopted. Operation Inputs the CPP switch on/off signal to the PCM. The contact point is on and voltage ...

Engine Coolant Temperature (ECT) Sensor Removal/Installation
WARNING: When the engine is hot, it can badly burn. Turn off the engine and wait until it is cool before removing the ECT sensor. ECT Sensor No.1 1. Disconnect the negative battery cable.. 2. Remove the plug hole plate.. 3. Drain the engine coolant.. 4. Pull out the evaporati ...