Troubleshooting

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





DETECTING CONDITION

WIRING DIAGRAM
Refer to Insufficient Coolant Temp. for Closed Loop Fuel Control on.






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 at 50 ~ 65 km/h (31 ~ 40 mph) for 1 ~ 3 minutes to warm up the heated oxygen sensor.
(5) Let the engine idle for 1 minute.

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.

INSPECTION PROCEDURE

HINT:
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 OBDII scan tool or LEXUS hand-held tester.