In Closed loop mode, the ECU can make adjustments to the idle control motor duty based on RPM feedback.This table should still be set so that the amount of Base Output results in your actual engine RPM matching your Target RPM. However, when it is not correct, the Short Term Trim will add or subtract an amount to try and make the RPM and Target match. Long Term can be used also to adjust this table over time based on short term corrections. Up to 3D mapping is available.