Monitor Description
The ECM monitors the idling speed and idling air flow volume to conduct Idle Speed Control (ISC). The ECM determines that the ISC system is malfunctioning if the following conditions are met:
- The difference between the target engine idling speed and actual engine idling speed exceeds the threshold and the IAC flow rate learned value is stuck at the upper or lower limit for 5 seconds or more.
- After driving at a vehicle speed of 6.25 mph (10 km/h) or more, the actual engine idling speed varies from the target idling speed by more than -100 RPM or 150 RPM or more when the A/C and NSW are off, or more than -100 RPM or 200 RPM or more when the A/C or NSW are on, 5 times or more during a driving cycle, the ECM illuminates the MIL and sets the DTC.