The desired set speed is adjusted down by momentarily depressing the SET/COAST switch. This is the TAP DOWN FEATURE. To be considered a valid TAP DOWN request, the SET/COAST switch must be pressed between 0.06 and 1 second. Each press of the SET/COAST switch (which is determined to be a valid TAP DOWN request) will cause the desired set speed to be decreased by 2 km/h (1 mph).