Mazda CX-5 Service & Repair Manual: Heated Oxygen Sensor (HO2 S) Heater Control

Mazda CX-5 Service & Repair Manual / Engine / Control / Heated Oxygen Sensor (HO2 S) Heater Control

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

Engine Coolant Temperature (ECT) Sensor

Purpose/Function Detects the ECT as basic information for mainly determining the fuel injection amount. Detects the ECT and inputs it to the PCM as an ECT signal. The ECT sen ...

Heated Oxygen Sensor (HO2 S) Inspection

HO2S Inspection 1. Connect the M-MDS to the DLC?2. 2. Switch the ignition ON (engine on). 3. Warm up the engine to normal operating temperature. 4. Access the following PIDs using the M-MDS.. ...

Other materials:

Body Panel
Outline The multi-load path and triple H-shaped structure of distributing the power absorbed at the collision were used for the body shell. A ring structure has been adopted for the triple H structure, realizing top-level crash safety performance. Crushable structure fro ...

Rear Drive Shaft Disassembly/Assembly
1. Disassemble in the order indicated in the table. 2. Assemble in the reverse order of disassembly. 1 Boot band (differential side) (See Boot Band (Differential Side) Disassembly Note.) (See Boot Band (Differential Side) Assembly Note.) 2 ...

Seat Belt
Fastening the Seat Belt Position the lap belt as low as possible, not on the abdominal area, then adjust the shoulder belt so that it fits snugly against your body. Unfastening the Seat Belt Depress the button on the seat belt buckle. If the belt does not fully retract, pull it out and che ...