Ignition Off Position

Ignition Off Position

When the ignition is switched off, the ECM keeps the main relay energised for 30 seconds. During this time the stepper motor is indexed to 180 steps (fully open).

The MEMS idle control is an adaptive system and the ECM learns the engine load and wear characteristics over a period of time. The amount of IACV steps required to maintain the specified idle consequently will differ from model to model. In the event of a new ECM or an ECM from another vehicle being fitted, it will take a short time of normal driving for the ECM to learn the load and wear characteristics of that engine.