Accent L L4-1495cc 1.5L SOHC MFI (2001)
Oxygen Sensor: Testing and Inspection
HEATED OXYGEN SENSOR (HO2S)- SINGLE HO2S
The heated oxygen sensor senses the oxygen concentration in the exhaust gas, then converts it into a voltage and then sends this to the ECM. The heated
oxygen sensor gives an output of about 800 mV when the air fuel ratio is richer than the theoretical ratio and output of about 100 mV when the ratio is
leaner (higher oxygen concentration in exhaust gas.) The ECM controls fuel injection based on this signal so that the air fuel ratio is maintained at the
theoretical ratio.
Circuit Diagram
TROUBLESHOOTING HINTS
1. If the heated oxygen sensor is defective, abnormally high emissions may occur.
2. If the heated oxygen sensor check is normal but the sensor output voltage is out of specification, check for the following items related to the air
fuel ratio control system:
-
Faulty injector.
-
Air leaks in the intake manifold.
-
Faulty mass air flow sensor, purge valve and engine coolant temperature sensor.
-
Wiring connection problem.
Using Voltmeter/Hi-Scan
NOTE:
If you release the accelerator pedal suddenly after engine running about 4000 rpm, fuel supply will stop for short period and the O2 sensor service data
