Here's a photo of the area just north of the PSU components.
The pair of blue jumpers (upper left) should measure 5.0 - 5.5VDC. If not, remove the jumpers, and measure from the right-hand pair of pins there. If still not, then the 5V supply is not working.
The single black jumper (upper right) beside that metal tab thingie is for the +3.3V supply. Again, it should measure about 3.3VDC. If not, remove the jumper and measure from the topmost pin. If still not 3.3V, then the 3.3V supply is not working.
That'll do for starters..
hi mlord.
finally found the time to check the voltages on the jumpers, here's the results...
i put the posi probe on the pin, and the neg on the outer casing of the psu plug, a couple of strange things happened when the probe pin touched both the psu input and empeg case together,
i'll try to explain...
when i simply go + to the jumper and - to the black neg wire on the pcb power in (big white rear right - screen facing you) it reads 9.4v, this is on 3v and 5v jumpers.
now, if i use the outer side of the psu plug to ground the _ probe, the same readings are apparent, but, if i let the - probe touch the chassis, it seems to damp the voltages down to what they should be. a small red surface mount led comes on (forward right corner) and a blue led (facing outward from rear centre).
nothing else seems to happen though, no boot screen, power up, etc.
my wild guess might be that there's an earthing fault somewhere?
any idea's welcomed!
regards.
Hugh
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