Idle Boost Functions
The DIM sends a serial data request to the (PCM, ECM) to increase the idle speed. The (PCM, ECM) then adjusts the idle speed by using a special program and idle speed ramp calculations in order to prevent driveability and safety concerns. The idle speed boost and cancel function will vary from vehicle to vehicle and from one moment to another on the same vehicle. This happens because the (PCM, ECM) responds to changes in the inputs from the sensors used to control the powertrain.