Idle Speed Control

ECM controls engine idle speed according to engine operating conditions and component/model application. ECM will send a signal to adjust and compensate for idle speed under the following conditions (if applicable on system): from starting to 20 seconds after start, low battery voltage, headlights on, heater switch on, A/C switch on, rear defogger on, power steering oil pressure switch on, radiator fan switch on, during deceleration and when vehicle is moving at idle. ECM will also send voltage signal to one or more of the following components as applicable.

• AAC Valve, IAC Valve, Fast Idle Control Device (FICD), Air Regulator