| WARNING | Read service precautions before proceeding with service procedure. See SERVICE PRECAUTIONS . |
Circuit Description
Idle speed is controlled by Electronic Throttle Control System (ETCS). ETCS uses throttle control motor to operate throttle valve opening angle to obtain target idle speed. DTC is set when idle speed continues to vary greatly from target speed. Possible causes are
- Defective ETCS.
- Air induction system malfunction.
Diagnostic Aids
Using Toyota hand-held tester or scan tool, read FREEZE FRAME data. Freeze frame data records engine conditions when malfunction is detected.