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:

Low Engine Coolant Temperature Indicator Light (Blue)/High Engine Coolant Temperature Warning Light (Red)
Purpose Low engine coolant temperature indicator light (blue) The low engine coolant temperature indicator light (blue) notifies the driver that the engine coolant temperature is low and vaporization of the fuel is difficult. High engine coolant temperature warning light (red) ...

Electronic Control Coupling
Purpose, Function An electromagnetic clutch, which operates smoothly due to the lack influence from the front and rear wheel traction force, has been adopted for the electronic control coupling system. Construction The construction of the coupling enables the torque formed ...

Spark Plug Inspection [Skyactiv G 2.0]
Specification Spark plug type PE01-18110, PE02-18110 Plug Gap Inspection CAUTION: To avoid possible damage to the tip, do not adjust the plug gap. To prevent damaging the tip, use a wire type plug gap gauge when inspecting the plug gap. 1. Measure the spark p ...