Hi Rifaa, I know this is a long dead thread, but I have a similar problem and was wondering if you could help me? I accidently connected 12v to the B- rail, and suspect a diode blown somewhere however there is no visibly blown component. I'm very embarrassed at having made this mistake. I would really appreciate your help. I have some technical knowledge, but not enough to nail this problem down. I have followed this thread all the way through with my dmm and found one or two differences in my readings, but I don't know what to do with this information, I really hope you can help.
ps my wife is shouting at me for wasting our money on a psu and then blowing it up, if I fix it she might forgive me
ps my wife is shouting at me for wasting our money on a psu and then blowing it up, if I fix it she might forgive me