Adjust GEZE Door Closer: Locate Final Closing Phase & Force Adjustment Screw for Unknown Model

As in the topic I am looking and looking for and find nowhere I can not add that the door closer is a company geese, what model I do not know, maybe someone will tell you where you need to emphasize so that at the end of the phase it is closed, I know that there is one screw under the cover but it probably serves for the closing force and I don't know where the final closing phase adjustment is

Turn this screw, look for the moment when the shock absorber no longer works, from that moment only the spring pushes and the closing force (door slam) is determined by the distance between the door and the frame.
Sometimes you have to sit for 20 minutes or so on this.

but when this screw or the door flies and closes with full force or I adjusted it very slowly so that it closes calmly, but the closing phases as such do not exist

There should be such a momet that they have been flying for some time, or look for another screw.

There is only one screw under the metal cover. on the right side of the door closer there are two holes, maybe these holes can be adjusted, but what to put in there to regulate

Well, try with an allen or a cross.

It's been a while since this post was opened, but I think there are a lot of people who have trouble adjusting the door closer. Therefore, I will try to help.
There are a lot of different models of door closers on the market, they differ depending on the purpose: size, closing force and the number of adjustment steps. Let's deal with the simplest ones, which have one or two "screws" for adjustment.
To adjust the door closer:
1. Remove the door closer.
2. Locate the adjusting screw (star screwdriver or a small flat screwdriver, eg electric indicator). If there are two adjustment screws, one is responsible for closing the wide-open door and the other for closing the final closing phase.
3. Open the door approx. 90 degrees and screw in the adjusting screw as far as it will go, the door will stop.
4. Slowly unscrew the adjustment until the door starts to move, by unscrewing the adjusting screw set the closing speed, approx. 5 seconds from an angle of 90 degrees.
5. Use the second screw to adjust the compression phase until the desired results are obtained.
6. If there is only one regulation, we regulate the closing phase by changing the angle of the door closer. With the door closed, loosen the M6 screw with a 10 mm key located under the two elements of the arm (V-shaped) and stretch the arm of the door closer towards the handle (if you want to shorten the tapping stroke) or the other way if you want to lengthen it. And we counter the screw.
Often, for example, doors in staircases are located one behind the other, then when closing the first door (when the second is closed) an airbag is created that inhibits the door closer, while when the second door is open the door closer "collapses" in this situation it is very difficult to adjust door closer. You can try by increasing the spring tension of the door closer. At the front or side of the door closer, there should be a screw under the hexagon socket, which, by screwing in, tension the spring, Do not overdo it "so that a child or an old woman has the strength to open the door.
When adjusting, you should also pay attention to whether the door does not have unnecessary resistance when closing, e.g. it does not rub on the floor, or the lock tongue is not protruding too much.
If the above advice does not bring results, we should ask for help from "Mr. Kazio's friend" or call the service.

And if in the DC240 door closer, when turning the C and L screws, there is no change in the closing force, the door closer is still to be saved.

Added after 42 [minutes]:

A week ago, I adjusted the door closer without any problems. Today no adjustment was working on the L and C screws. After disassembling the door closer, I was able to easily adjust it on the L and C screws. Can the DC240 door closer be serviced in any way, ie add hydraulic fluid?