Idle Speed Control (ISC) System
• The idle speed control system controls the idle speed by regulating the injection quantity in order to match the actual speed to the target speed calculated by the computer. The ISC can be automatic ISC or manual ISC.
Automatic ISC
– With automatic ISC, the engine ECU sets the target speed. The target engine speed varies with the type of transmission (automatic or manual), whether the air conditioner is ON or OFF, the shift position, and the coolant temperature.
Manual ISC
– The idle engine speed is controlled by the setting on the idle setting button at the driver’s seat.
Idle Vibration Reduction Control
– This control reduces engine vibration during idle. To achieve smooth engine operation, it compares the angle
speeds (times) of the cylinders and regulates injection quantity for each individual cylinder in the event of a large difference.
