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:

Precaution
Intermittent Concern Troubleshooting Vibration method If a malfunction occurs or becomes worse while driving on a rough road or when the engine is vibrating, perform the following steps. NOTE: There are several reasons why vehicle or engine vibration could cause an electr ...

Throttle Position (TP) Sensor Inspection
Voltage Inspection CAUTION: The inspection cannot be performed with this method correctly if there is a malfunction of the APP sensor or throttle valve actuator. Verify that no DTCs related to the APP sensor or throttle valve actuator are stored before the inspection. NOTE: ...

Purge Solenoid Valve Removal/Installation
1. Disconnect the negative battery cable.. 2. Remove the plug hole plate.. 3. Remove the air cleaner and air hose as a single unit.. 4. Disconnect the high pressure fuel pump connector. 5. Disconnect the harness clip as shown in the figure. 6. Remove in the order indicated in the table ...