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 apply:
- The learned idling air flow volume remains at the maximum or minimum volume for 5 seconds during a drive cycle.
- While driving at 10 km/h (6.25 mph) or more, the actual engine idling speed varies from the target idling speed by between 100 RPM and 150 RPM, 5 times or more during a drive cycle.
Example:
If the actual idle RPM varies from the target idle RPM by more than 150 RPM* 5 times during a drive cycle, the ECM will turn on the MIL and a DTC is set.
HINT:
*: RPM threshold varies with engine load.