mvs repair guide

Hi folks,

I have required some mvs 4 slots and after reading about cross hatches and green screens for the past few days I was wondering if there is a guide on where to start with repairing these boards. I only find repair logs of existing problems. Not a guide on how to go about checking everything step by step, what to check first, what should be viewed when any of the dip switches are on/off, what the significance is of the coloured screens, how to do test on the boards sepperately,...

I have a unibios coming my way and will be starting with replacing the batteries and checking the psu. Just looking for more info.

cheers guys and thanks

if you're stucked in crosshatch, look at the signal SYSTEMB, pin 54 of the NEO, it should probably connected to AS04(6)
and the input of the AS04(5) come from NEO-IO(19) and is also connected to a 74HC259.
Check continuity.
Green screen is related to Quartz 32.768 KHz, NEO-F0 and a NEC 4990 chip.