Electronic Idle Speed Control

Idle speed ECU is integrated in CIS-E ECU but is functionally separate from CIS-E. Idle speed air valve, located in throttle valve by-pass hose, receives signals from idle speed ECU.

Functions of the idle speed control system are extended by the air flow sensor voltage signal. As a result, the control unit recognizes the momentary airflow rate. In combination with the engine speed, the position of the microswitch and the coolant temperature, the activation of the idle speed air valve and thereby the idle speed will be determined.

When ignition is switched on, idle speed ECU is energized. Electronic control system will generate basic frequency of 100 Hz.