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Monitor Description

The ECM detects idle speed and idle air flow amount for Idle Speed Control (ISC). The ECM concludes that the ISC is malfunctioning if: 1) the learned value of the ISC remains at the maximum or minimum 5 times or more during a drive cycle, and 2) while driving at 10 km/h (6 mph) or more, the actual idle RPM varies from the target RPM by -200 to -100 RPM or 100 to 200 RPM 5 times or more during a drive cycle.

Example:

If the actual idle RPM varies from the target idle RPM by more than 200 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.

Fig 1: Idle Speed Graph
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