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:

Drive Belt Removal/Installation
WARNING: A hot engine can cause severe burns. Turn off the engine and wait until it is cool before servicing. NOTE: Remove/install the drive belt from the underside of the vehicle. Generator Drive Belt Removal/Installation CAUTION: To prevent damage to the dri ...

Rear Stabilizer Control Link Inspection
1. Remove the rear stabilizer control link.. 2. Inspect for bending or damage. If there is any malfunction, replace the rear stabilizer control link. 3. Rotate the ball joint stud 10 times and shake it side to side 10 times. 4. Measure the ball-joint rotational torque using an Allen wrench ...

Winter Driving
Carry emergency gear, including tire chains, window scraper, flares, a small shovel, jumper cables, and a small bag of sand or salt. Ask an Authorized Mazda Dealer to perform the following precautions: l Have the proper ratio of antifreeze in the radiator. • Inspect the battery and its cable ...