Roland xf 640 print test (black line)

[Atef]

Hello, please who can help.
There is a thin vertical black line in the test print in the head (B) test.
The head (B) was not working and i had to change one head print and headboard and cartridge board to get this result.
So what is the problem of the black line now ?

 

[Val47]

Show us what it looks like. Post a picture

 

[Atef]

Show us what it looks like. Post a picture

Thank you for replying, i have changed the headboard and the problem solved, but i don't know if the board can be fixed or no