How to Test a DC Jack?

Archived from groups: comp.sys.laptops,sci.electronics.repair (More info?)

In article <1121872115.222144.148410@g49g2000cwa.googlegroups.com>,
<ey.markov@iname.com> wrote:
> when the DC jack on my Sony Vaio FXA32 broke, I got the motherboard out
> and soldered in a new jack. Put the MB back into the case, plugged it
> in, attached the LCD, and it POSTed. Happily I re-assembled the laptop,
> only to find that in order for the adapter to power the laptop, I had
> to push it in and hold it tight. After a while that stopped working,
> too.

Sure you got the right type? I've come across ones with the same OD to the
plug - say 2.1mm - but the centre pin ain't the same size on both. Might
be worth getting a plug from the same source and changing that too.

Hate the things. ;-)

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Archived from groups: comp.sys.laptops,sci.electronics.repair (More info?)

ey.markov@iname.com wrote:
> Greetings,
>
> when the DC jack on my Sony Vaio FXA32 broke, I got the motherboard out
> and soldered in a new jack. Put the MB back into the case, plugged it
> in, attached the LCD, and it POSTed. Happily I re-assembled the laptop,
> only to find that in order for the adapter to power the laptop, I had
> to push it in and hold it tight. After a while that stopped working,
> too.
>
> The unit runs fine off the battery, so I haven't fried anything. But
> how do I find out what the problem is now? Is it the replacement jack,
> or the way it's been soldered in? It looked fairly straightforward, and
> the fix did work the first time...
>
> Thanks,
>
> Yisroel
>

I don't have any experience with that exact model.

But plugs rarely break. What breaks is the connection to the board.
You may still have cracked traces that disconnect when flexed.
Did you use the EXACT replacement part from sony.
Slightly different inner/outer diameters can cause what you experience.
Are you sure the problem wasn't in the plug end? Plugs get more flex
and the wire tends to break right at the end of the strain relief.
mike

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Archived from groups: comp.sys.laptops,sci.electronics.repair (More info?)

jakdedert wrote:
> ey.markov@iname.com wrote:
> > Greetings,
> >
> > when the DC jack on my Sony Vaio FXA32 broke, I got the motherboard
> > out and soldered in a new jack. Put the MB back into the case,
> > plugged it in, attached the LCD, and it POSTed. Happily I
> > re-assembled the laptop, only to find that in order for the adapter
> > to power the laptop, I had to push it in and hold it tight. After a
> > while that stopped working, too.
> >
> > The unit runs fine off the battery, so I haven't fried anything. But
> > how do I find out what the problem is now? Is it the replacement jack,
> > or the way it's been soldered in? It looked fairly straightforward,
> > and the fix did work the first time...
> >
> In addition to the suggestions already made,

Many thanks to those who responded.

Dave and Wayne, I checked the prongs on the jack with the AC adapter
plugged in. It does supply the voltage, so the jack *is* compatible
with the adapter. (I should've done this first.)

Mike, it *was* the jack that broke - the plastic receptacle for the
center pin just disintegrated into shards.

> be aware that the circuit board
> in your laptop contains many layers. Each has it's own traces (conductors).
> Think of a regular double-sided circuit board (conductors on each
> side)...then imagine two or three of them sandwiched together, with some
> components (like the power jack) needing to be connected to traces on more
> than one layer. It's sometimes a little more difficult than soldering just
> the conductors you can see, although, ideally each such hole should be
> 'plated through'; meaning the inside of the hole has it's own layer of
> copper and connects to each layer.
>
> You might have missed one layer, and when you hold the plug 'just so' it
> makes mechanical contact.

This sounds like the most likely culprit. The ends of the prongs that
stick through the board I have soldered solid, but that doesn't mean
that there's contact inside the board. Damn. Guess I'll have to get the
thing out and try to plate the insides of the holes with solder or
something. Oh well...

Yisroel

Archived from groups: comp.sys.laptops,sci.electronics.repair (More info?)

Use a MultiMeter to ring it out before you put it all back together. Another
thing to watch out for is you accidentally heated up a component near by and
made it loosen up. Been there and done that.

Dewaine

jakdedert wrote:

> ey.markov@iname.com wrote:
> > jakdedert wrote:
> >> ey.markov@iname.com wrote:
> >>> Greetings,
> >>>
> >>> when the DC jack on my Sony Vaio FXA32 broke, I got the motherboard
> >>> out and soldered in a new jack. Put the MB back into the case,
> >>> plugged it in, attached the LCD, and it POSTed. Happily I
> >>> re-assembled the laptop, only to find that in order for the adapter
> >>> to power the laptop, I had to push it in and hold it tight. After a
> >>> while that stopped working, too.
>
> <snip>
> >> You might have missed one layer, and when you hold the plug 'just
> >> so' it makes mechanical contact.
> >
> > This sounds like the most likely culprit. The ends of the prongs that
> > stick through the board I have soldered solid, but that doesn't mean
> > that there's contact inside the board. Damn. Guess I'll have to get
> > the thing out and try to plate the insides of the holes with solder or
> > something. Oh well...
> >
> > Yisroel
>
> I only put it out there as one likely culprit along with the suggestions of
> the other repliers; but it's worth investigating.
>
> jak