Which of the following is NOT a function of the regulator in a vehicle?

The function of the regulator in a vehicle primarily involves the mechanical operation of the windows. It is responsible for controlling window movement and maintaining window position as they open and close. The regulator works in conjunction with the window motor to provide the power necessary to move the window up and down.

While a regulator is integral to the proper functioning of power windows, sealing the edges of the window does not fall under its responsibilities. Sealing is typically managed by the window's weatherstripping or seals, which ensure that windows fit tightly against the frame to protect the interior of the vehicle from water and air leaks. Therefore, sealing the window edges is not a function of the regulator, making that answer correct.