Where are eMachine fuses location?
Computer acts like a fuse is blown. I took the power supply apart
and can't find one in there, or the motherboard, or anywhere else.
Can anyone point me in the right direction?
The fuse is usually a glass cylinder about 5mm in diameter and 20mm
long, with silver-colored metal caps on the ends. Most are soldered
directly to the circuit board, but some are held in place by metal
clips, and a few are
installed upright and have a wire going form the top metal cap to the
board. The latter may even be completely enclosed in heatshrink
tubing, typically dark grey. But just replacing a blown fuse rarely
restores operation since they usually fail only when something else in
the supply fails, typically the high voltage transistors (on the
heatsink next to the large cylindrical capacitors), the coupling
capacitor to the transformer (usually shows charring and cracking),
one of the electrolytic capacitors on the low voltage side, or a
shorted diode on that side. See
www.nutsvolts.com/PDF_Files/PSRepair.pdf .
Do NOT diagnose the power supply while it's plugged into the AC
because this creates a major high voltage hazard and is unnecessary
because everything can be tested with the power removed. If you need
to replace a transistor or diode, you'll have to desolder all the
components on its heatsink assembly, possibly including the heatsink
itself. Take precautions with the insulation of heatsinks (any
mounting screws may have a nylon or fiber washers between them and the
circuit board), transistors, and diodes (they often need flanged nylon
washers plus thin insulator sheets).
