The invention relates to a method for adjusting the operating temperature of a control device (2) of the gearbox of a motor vehicle, especially of an automatic gearbox. The invention further relates to the control of a gearbox having an electronic unit (4) with electronic modules and a hydraulic unit (3). Said control device (2) is arranged in a gearbox case which is partially filled with gear lubricant oil and which is at least partially surrounded by oil. The control device (2) has a cooling device (5) which cools the at least one part of the electronic unit (4) of the control device (2) by means of a coolant with a temperature υ_c which is smaller than the prevailing temperature of the gear lubricant oil υ_G. According to the invention, the electronic unit (4) is impinged upon with a predetermined volume flow of the coolant.