JFC macs are not as reliable as I remember them. I bought my parents a used 2008 model last summer and it lasted four months before the video card packed in, so that was core exchanged for another refurbished unit that lasted until yesterday when my mother came into the room and it was stone dead. 
Logic board LED's are all off and no DC voltages were found on the PSU output but AC was found being delivered to the input. F1 and F2 show continuity.
The large 150MFD 420v lytic had puked out from the positive cap leg. All other capacitors were visually okay and had good ESR. This is apparently a common fault and a single cap replacement repairs it however not this time.
All I have on hand that will fit is a 150mfd 400v so that was substituted as the circuit shouldn't mind the lower voltage rated cap. Still no life. I can't even find a voltage at the primary cap. The fault has to be in the primary somewhere, but after the bridge rectifier or F1 would be completely toast.
I am seeing about 4.7 ohms across the primary cap for resistance which seems oddly low but I believe that's just a thermistor trying to throw me off.
Google is basically useless for ANY support for Apple components, every mention of the iMac PSU or the Hipro HP-N1700XC are "open machine and replace psu" like I'm some sort of dimwit.
Logic board LED's are all off and no DC voltages were found on the PSU output but AC was found being delivered to the input. F1 and F2 show continuity.
The large 150MFD 420v lytic had puked out from the positive cap leg. All other capacitors were visually okay and had good ESR. This is apparently a common fault and a single cap replacement repairs it however not this time.
All I have on hand that will fit is a 150mfd 400v so that was substituted as the circuit shouldn't mind the lower voltage rated cap. Still no life. I can't even find a voltage at the primary cap. The fault has to be in the primary somewhere, but after the bridge rectifier or F1 would be completely toast.
I am seeing about 4.7 ohms across the primary cap for resistance which seems oddly low but I believe that's just a thermistor trying to throw me off.
Google is basically useless for ANY support for Apple components, every mention of the iMac PSU or the Hipro HP-N1700XC are "open machine and replace psu" like I'm some sort of dimwit.
<----Computer says I need more beer.
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