Component Location
Description
1. General Description

The rear heated oxygen sensor is mounted on the rear side of the Catalytic Converter (warm-up catalytic converter) or in the rear exhaust pipe, which detects the catalyst efficiency. The rear heated oxygen sensor (HO2S) produces a voltage between 0V and 1V. This rear heated oxygen sensor is used to estimate the oxygen storage capability. If a catalyst has good conversion properties, the oxygen fluctuations are smoothed by the oxygen storage capacity of the catalyst. If the conversion provided by the catalyst is low due to aging, poisoning or misfiring, then the oxygen fluctuations are similar to signals from the front oxygen sensor.

2. DTC Description

If circuit voltage is higher than 4.5V after 5V is applied to the HO2S output line via a resistor, the ECM judged as a open circuit and DTC is set.

DTC Detecting Condition

Item

Detecting Condition

Possible cause

DTC Strategy

● Circuit voltage(Vf) is monitored.

● Poor connection

● Open in HO2S circuit

● Defective HO2S

● Defective ECM

Enable Conditions

● Engine coolant > 81℃(177.8℉)

● Engine speed >1187rpm

● Load value >300mmHg

Threshold value

● Circuit voltage after applying 5V to sensor ≥ 4.5V

Diagnosis Time

● Continuous

MIL On Condition

● 2 driving cycles

Schematic Diagram
Яндекс.Метрика