I have a Roland vp 540 and was working fine. 3 days later I turned on and no power to the control panel .. it is getting power to the machine as the green light comes on when back switch is on ... I replaced the ribbon cable . From the control panel. Still won’t come on .. checked the voltage with a meter from the power board out and into the board was fine ... in checking with a meter there is a small set of wires on the bottom left. 2 black and one red and one orange that does not have power .. it goes from servo to main .. so now my problem comes. Do I repair or replace the servo or the main Not sure how to check or if it is just trial and error .. is there a reputable repair company .. also when I replace the boards do I need a service manual for codes or can I plug and play .. I am closed at the moment so money is tight But really need my machine .. any help or ideas would be appreciated .. thank you