Troubleshooting

CIRCUIT DESCRIPTION
Refer to Insufficient Coolant Temp. for Closed Loop Fuel Control.





DETECTING CONDITION
Bank 1 refers to the bank that includes cylinder No.1.
Bank 2 refers to the bank that does not include cylinder No.1.
Sensor 1 refers to the sensor closer to the engine body.
The heated oxygen sensor's output voltage and the short-term fuel trim value can be read using the OBD II scan tool or LEXUS hand-held tester.











INSPECTION PROCEDURE





CONFIRMATION DRIVING PATTERN
(1) Connect the LEXUS hand-held tester to the DLC3.
(2) Switch the LEXUS hand-held tester from normal mode to check mode.
(3) Start the engine and warm it up with all accessory switches OFF.
(4) Drive the vehicle at 50 ~ 65 km/h (31 ~ 40 mph) for 13 min. to warm up the heated oxygen sensor.
(5) Let the engine idle for 1 min.

HINT: If a malfunction exists, the MIL will light up during step (5).

NOTICE: If the conditions in this test are not strictly followed, detection of the malfunction will not be possible.

If you do not have a LEXUS hand-held tester, turn the ignition switch OFF after performing steps (3) to (5), then perform steps (3) to (5) again.