Hi! This one is more of a personal challenge, I could not find the schematics nor boardview files, so here it comes. Bought very cheap, not working, start troubleshooting, AC adapter plug in, dc cable plug in, no green light, ON/Off button does not work, 3.3V and 5V present, no 3.42 or any other voltage present. On/Off buttton have 3.3v on one pin, if I short to ground, voltage drops. Because of no schematics I don't know which power supply is which, by guessing I start to measure voltage on one IC, ISL6269CRZ, U7800, probe slip from pin 1 Vin to pin 2, Vcc, magic smoke escape from U7800. After that I get very low resistance on coil to ground, upper Mosfet is shorted, I take out both transistor, short remain. So, if anybody know what U7800 is doing on this board, please share, because if this cip generates any voltage that goes stright to ICH or SMC is game over for this board. Also if anybody know which cip generates PPBUS_G3H, please share, I suspect another cip which also have low resistance on coil to ground measure. Many thank's, best regards!
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Re: Mac mini 2006-2007 820-1900-a, won't start, no green light, etc!
first pic, U7800, second ,Mosfets, third, mainboardAttached Files -
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Re: Mac mini 2006-2007 820-1900-a, won't start, no green light, etc!
2168 is shortedComment
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Re: Mac mini 2006-2007 820-1900-a, won't start, no green light, etc!
Sorry, I didn't realized is a desktop computer. Thank's!Comment
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