オリジナル投稿者： Roger ,
Why logic board chimes when pin is touched with probe?
Hello Guys, Maybe one of you can help with this unusually weird problem I have with my 820-2330 logic board. The board powers on, but won't chime or boot until I touch a couple of specific pins on chip U8900. This is what happens exactly; when the board is powered on and I touch pins VO or OCSET on U8900 the board then chimes and boots normally. It is driving me crazy trying to figure this one out. At first I replaced U8900, then I replaced both FETS, then I replaced the Critical caps after the inductor all to no avail. Any help would be appreciated. Thanks, Roger
Macbook pro 2008 Logic board 820-2330A