@girhoobin Volvo doesn't offer ACC for manual cars for security reasons as there is a very realistic risk to stall your engine when ACC is decreasing the speed too much. You might be able to enable the parameter with Vdash anyway.
But it's definitely a serious traffic security risk to enable it in a manual car, as a suddenly stalled engine while driving means almost no brakes and a highly distracted and panicing driver who tries to restart his engine or doesn't even know what to do while the car is still rolling, and therefore it's absolutely not recommended as you are threating your own life as well as the lifes of everyone around you.