Kia Rio: Engine Control System / Heated Oxygen Sensor (HO2S)

Specifications

Specification

Heated Oxygen Sensor (HO2S)

HO2S [Bank 1/Sensor 1]

Item	Specification
Heater Resistance (Ω)	Approximately 9.0 [20°C(68°F)]
Type	Binary
Pin	4

HO2S [Bank 1/Sensor 2]

Item	Specification
Heater Resistance (Ω)	Approximately 9.0 [20°C(68°F)]
Type	Binary
Pin	4

Description and operation

Description

Heated Oxygen Sensor (HO2S) consists of zirconium and alumina and is installed on upstream and downstream of the Warm up Catalytic Converter (WCC).

After it compares oxygen consistency of the atmosphere with the exhaust gas, it transfers the corresponding voltage signal to the ECM. When A/F ratio is rich or lean, it generates approximately +1V or 0V respectively.

In order that this sensor normally operates, the temperature of the sensor tip must be higher than predetermined temperature. So it has a heater which is controlled by the ECM duty signal. When the exhaust gas temperature is lower than the specified value, the heater warms the sensor tip.

Schematic diagrams

Circuit Diagram

Repair procedures

Inspection

1.	Check signal waveform of HO2S using a KDS/GDS. Specification : Refer to "Waveform"

2.	Turn the ignition switch OFF.

3.	Disconnect the HO2S connector.

4.	Measure resistance between HO2S heater terminals 3 and 4.

5.	Check that the resistance is within the specification. Specification: Approximately 9.0 Ω [20 °C (68 °F)]

Removal

Note that the SST (Part No.: 09392-2H100 or 09392-1Y100) is useful when removing the heated oxygen sensor.

1.	Turn the ignition switch OFF and disconnect the battery negative (-) terminal.

2.	Disconnect the connector (A), and then remove the sensor (B). Heated oxygen sensor installation: 39.2 - 49.1 N.m (4.0 - 5.0 kgf.m, 28.9 - 36.2 lb-ft) [Bank 1 / Sensor 1] [Bank 1 / Sensor 2]

Installation

• Install the component with the specified torques. • Note that internal damage may occur when the component is dropped. In this case, use it after inspecting. • DON’T use a cleaner, spray, or grease to sensing element and connector of the sensor because oil component in them may malfunction the sensor performance. • Sensor and its wiring may be damaged in case of contacting with the exhaust system (Exhaust Manifold, Catalytic Converter, and so on).

1.	Installation is reverse of removal.

Troubleshooting

Waveform

[Sensor 1, 2]

[Bank 1 / Sensor 1]

[Bank 1 / Sensor 2]