Versacamm SP 540V Doesn't print

Hey all. Was wondering if anyone else has had this problem. Recently my magenta and yellow printer head on my Versacamm SP 540 V stopped working. Without knowing much about the system and random googling-- I replaced both the cap tops and the magenta and yellow printer head. ( printer heads are so expensive) But to no avail. My yellow ad magenta still doesn't print. And then suddenly my cyan and black printer head went out too. Now during a test print I get nothing. I think it's the cartridge printer circuit board. Am I jumping to conclusions again? Any help would be greatly appreciated! Thanks!