Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems.

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nospam_needed
 
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Default Reading capacitance on SM capacitor



Hi,

I'm looking at a laptop (Toshiba Sat 3000, to be specific) motherboard
that having some SMD suspecting leaky capacitors; Some basic questions
if someone can bring me up-to-date to the world of surface mount device,
that would be nice:

* There are four of them in parallel; ohm reading both way, in circuit,
about 50 Ohm. They are around the power charging area, and the circuit
having a blown fuse. Would this sound like a strong posibilty for leaky
cap ? (I can take them out one by one for sure...)

* The capacitors are the good size ones in the SMD world (6mmx4mmx3mm);
There is + sign printed on one end, and the printed note say "220" on
first line and "g14" the next line. Would that be 220 pF ? Seem little
for that size...

Thanks for any advice.

Cheers,

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Rono
 
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The best trick to use is heat one let of the capacitor
in question, & smell for a "fishy" smell. Rono.


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The caps may or may not be shorted or leaky..... you should remove one
leg so you can test them out of circuit. 220 MFd or 220 uF..... not
220pF
electricitym

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Jerry G.
 
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The capacitors must be removed to properly test them. Most likely there
are other components connected the capacitors, that are giving you the
resistance reading. Caps should be tested with both an ESR meter, and a
capacitance meter to truly have an idea of their performance.

Jerry G.
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