i just got a 6MDM with quite a few probs. I haven't bothered to extend diagnosis beyond the rectifier board ATM. start at the beginning and get the voltage train right first. test the test points on the -18 board first. these boards will almost always need a rebuild given their age, shitty design , underspeced components and old connectors.
Just give the board to Gavin - He LOVES Bally Power boards !
