Mamiya RB67 Pro S frame counter issue

I just purchased a Mamiya RB67 Pro S, of course with the Pro S film back.
Now matter how many times the film advanced lever is moved, the frame counter still
shows "S" (with the red indicator). Film winding is fine, though.

Before I bring this camera to a camera repair shop, is there anything I can to fix the problem myself?

are you handy? there are just 4 screws holding the top plate on. also, while you are at, change the light seals yourself.

counter problems are generally related to the signal arm or the roller directly geared to tge counter. the repair manual, which you can get from bukus.com, will explain.

you will just need a good crosspoint and a large flat screwdriver.

search apug, ive given directions here many times.