Diagnostic Trouble Code

Wiring Diagram:

CIRCUIT DESCRIPTION
ECM monitors oxygen concentration in the exhaust gas which has passed the three way catalytic converter by HO2S-2.

When the catalyst is functioning properly, the variation cycle of HO2S-2 output voltage (oxygen concentration) is slower than that of H02S-1 output voltage because of the amount of oxygen in the exhaust gas which has been stored in the catalyst.

Reference:

Reference

Detecting Condition / Trouble Area:

DTC CONFIRMATION PROCEDURE

WARNING:
- When performing a road test, 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, on a level road.

NOTE:
Check to make sure that following conditions are satisfied when using this DTC CONFIRMATION PROCEDURE.
- Intake air temp.: Between -14 °C and 70 °C (6.8 °F and 158 °F)
- Altitude (barometric pressure): 2400 m, 8000 ft or less (560 mmHg, 75 kPa or more)
- Fuel level indication on meter cluster: 114 or more (For 1999 MY)

1. Connect scan tool to DLC with ignition switch OFF
2. Turn ON ignition switch and clear DTC using scan tool.
3. Increase vehicle speed to 50 - 60 mph, 80 - 100 kph . (engine speed: 2500 - 3000 r/min.)
4. Keep above vehicle speed for 10 min. or more (Throttle valve opening is kept constant in this step).
5. Stop vehicle and check if DTC/pending DTC exists using scan tool. If not, check if catalyst monitoring test has completed using scan tool. If not in both of above checks (i.e., no DTC/pending DTC and catalyst monitoring test not completed), check vehicle condition (environmental) and repeat step 3. through 5.

Troubleshooting (Steps 1 - 3):