P0131

DTC P0131 HEATED OXYGEN SENSOR (HO2S) CIRCUIT LOW VOLTAGE (SENSOR-1)





WIRING DIAGRAM

CIRCUIT DESCRIPTION
The oxygen sensor-1 is installed on the exhaust manifold (pre-catalyst) and the oxygen sensor-2 is installed on the exhaust pipe (post- catalyst). Each sensor detect the concentration of oxygen in the exhaust gases.
ECM detects the air-fuel ratio of the mixture supplied to the engine by monitoring the signal (output voltage) from sensor-1. The signal (output voltage) from sensor-2 is used to detect malfunction of the three way catalytic converter.
Each oxygen sensor heater promotes activation of the oxygen sensor.





DETECTING CONDITION

DTC CONFIRMATION PROCEDURE

WARNING:
- When performing a road test5 select a place where there is no traffic or possibility of a traffic accident and be very careful during testing to avoid occurrence of an accident.
- Road test should be carried out with 2 persons, a driver and a tester.

1) Turn ignition switch OFF. Clear DTC with ignition switch ON, check vehicle and environmental condition for:
- Indication of fuel level meter in combination meter: 1/4 or more
- Altitude (barometric pressure): 2400m, 8000ft or less (560mmHg, 75kPa or more)
- Ambient temp.: -10°C, 14°F or higher
- Intake air temp.: 70°C, 158°F or lower
2) Warm up engine to normal operating temperature.
3) Drive vehicle at 30 - 40mph, 50 - 60km/h for 2 min.
4) Stop vehicle and run engine at idle for 2 min.
5) Check DTC in "DTC" mode and pending DTC in "ON BOARD TEST" or "PENDING DTC" mode.











INSPECTION