The Control pin (sometimes labeled C) is the . It works in tandem with the BMS to manage the flow of electricity.
The best way to confirm these functions is through systematic testing with a . The following readings were obtained by placing the black probe of a DMM on the B- (Negative) pin and using the red probe to measure voltage on the other pins. These readings were taken from a fully charged battery pack: Hart 20v Battery Pinout Diagram