Troubleshooting

CIRCUIT DESCRIPTION

The idle speed is controlled by the Electric Throttle Control System (ETCS).

ETCS is composed of the throttle motor to operate the throttle valve, the magnetic clutch to connect the throttle motor with the throttle valve, the throttle position sensor to detect the opening angle of the throttle valve, the accelerator pedal position sensor to detect the accelerator pedal position, the ECM to control the ETCS and the one valve type throttle body.

The ECM controls the throttle motor to make the throttle valve opening angle properly for the target idle speed.




DETECTING CONDITIONS

Step 1:

Step 2:

INSPECTION PROCEDURE

HINT: Read freeze frame data using LEXUS hand-held tester or OBD II scan tool. Because freeze frame records the engine conditions when the malfunction is detected, when troubleshooting it is useful for determining whether the vehicle was running or stopped, the engine warmed up or not, the air-fuel ratio lean or rich, etc. at the time of the malfunction.