Identifying the Real Problem (DC Jack)

[DanF]

Did it again, this time following your advise as much as possible.

At least this time I didn't get a blob, but rather soldering that's surrounding the jack's connections. The second picture shows solder is also visible from the other side. This means solder got through... although I might still have put excessive solder on some connections.

 

[NYJimbo]

Did it again, this time following your advise as much as possible.

At least this time I didn't get a blob, but rather soldering that's surrounding the jack's connections. The second picture shows solder is also visible from the other side. This means solder got through... although I might still have put excessive solder on some connections.

Looks better. After you do a bunch of these it will come natural to you. Don't beat yourself up if you make mistakes as you go along this is something you have to learn on your own and you don't get a lot of opportunity to practice. Just try to learn from any mistakes and always try to get results like you did (or better). I know people doing jacks who just blob the solder on the pins and think that's ok. What happens with those is the jacks can wiggle a bit and a tiny gap is created between the pins and the solder "cap" that the blob creates. Every time the customer inserts the DC plug to the jack a tiny spark occurs. Do that a hundred times and you end up with this:

 

[DanF]

I'm sure you will all appreciate this... but your help turned out to be fruitful as always. One final question: is there any way to test such a job?

 

[NYJimbo]

I'm sure you will all appreciate this... but your help turned out to be fruitful as always. One final question: is there any way to test such a job?

Do you mean test the result ? You can do two things:

1) Set a multimeter to continuity and probe the positive pin and the negative pins, you should NOT hear or see
any indication of a connection. If you do then something is shorted in the jack, the solder or the mobo. Sometimes
you will see a tiny fluctuation but it only lasts a split second. But if its a solid tone then you got a short.

2) You can plug the charger into the dc jack and probe the motherboard or jack to see if you got normal voltage.

Also keep in mind that MANY times both the jack AND the charger plug tip will be bad so you can do a new
jack and still have charging issue or wiggling the jack shows it faulty, so be sure to have your own chargers
to test the new jack.

ps- don't forget to click the "like" if all of this helped you.

 

[DanF]

In fact, even the charger was bad. I got nervous when it didn't power up, that's why it is half disassembled! Then I got out my multi-adapter and it worked fine. Fortunately enough I have a spare brand new Asus adapter for this model in stock.

Will do the 'like' round soon You sure deserve it

 

[NYJimbo]

This model looks very familiar. Did the center pin break off at the back of the jack right where it curves up from the motherboard ?

 

[DanF]

Bingo.

It's an Asus X54C

 

[NYJimbo]

Bingo.

It's an Asus X54C

99% of the time when that series comes for a jack in you will see the exact same failure point. Its weird because sometimes you take out the mobo and it looks perfectly normal and you don't know its broken right where it meets the jack because its held in place by the solder on the mobo, but when you desolder the center pin it just drops right out.

 

[DanF]

I noticed that. Since I used hot air, the jack just fell and that middle pin just stayed in its position.

 

[DanF]

A problem this notebook seems to have is interference between the mic and the speakers. When volume is up you can hear that squeaking (not sure if it's the correct term) noise it hurts your ears. I honestly don't know if this problem was there before the repair or not, but I can't imagine how this could have been caused during or after the repair. It's like when you move a mic just in front of a speaker.

 

[jbartlett323]

I'll give it another try. What if one of the blobs makes contact with the jack? Answers to your posts below:

I have a sponge not the steel-wool stuff.

I am putting some solder on the tip and clean it in the sponge before starting.

I did a mistake not to put any flux before soldering.

What do you mean by leaving solder on the entire tip when done? Does that mean that I should turn the iron off with solder on?

OK, get yourself a steel wool thingy. Part of your issue is that as soon as u touch a wet sponge to the tip, it cools off, then immediately oxidizes making heat transfer difficult. The other just pulls the solder off, not cooling the tip or pulling to much.

Yes, when you are done leave a healthy coating of solder to cool on your tip. This ensures your tip doesn't oxidize. Oxidization cause pits in the tip metal, therefore inhibiting thermal transfer. To keep your tip working for a long time, just tin the tip after each use and leave it on there!

Great job on that second try! You recognized the only thing I woulda said, little to much solder. But hey, good job, pat yourself on the back!
If u can though, grab a dead mobo and practice a couple times! Like jimbo said, won't be long its second nature!

 

[Larry Sabo]

Yes, when you are done leave a healthy coating of solder to cool on your tip. This ensures your tip doesn't oxidize. Oxidization cause pits in the tip metal, therefore inhibiting thermal transfer. To keep your tip working for a long time, just tin the tip after each use and leave it on there!

You should have some soldering iron tip refresher on hand for when that happens.
http://www.ebay.ca/sch/i.html?_odkw...er&_nkw=soldering+iron+tip+refresher&_sacat=0

 

[Markverhyden]

Did not notice this being mentioned. Just an observation. I would never use aluminum foil as a shield. Just like any other metal it has a very high thermal conductivity so offers very little protection. Not to mention it's electrical conductivity characteristics.

 

[NJW]

All valid points. One thing not mentioned, I think, is that it's important to clean the pins on the new socket before fitting. Any greasy (fingerprint) deposits or oxide on the surface of the pins will prevent the solder flowing through the hole. the same applies to the through-hole plating (see the burnt flux (?) remains in one of your earlier photos).

The main connection between the motherboard and the socket is frequently on the opposite side (i.e, the 'top') from where you apply the solder (the 'bottom') and you don't want all the power going through the through-hole plating material. Cleaning the pins will also get the solder to 'take' much more quickly.

A problem this notebook seems to have is interference between the mic and the speakers.

Running on battery? Running with battery+charger? Running with charger only? If only when the charger is plugged in, it could be a bad charger (most likely), but it could also be a poor power connection (e.g., supply impedance/board damage introduced by bad soldering ).

If it's always there check cable connections, cable routing and condition of any grounding tape/spring fingers.

 

[Mainstay]

I sometimes use a solder sucker, but find that solder bits sometimes fall from the opening onto the MB, which could cause a short if not thoroughly removed. If you get one, I'd suggest you get a good one and cut a small notch in the tip to make it more effective at getting the tip right into joints with through-hole leads.

Was I the only one aroused by that video?

Good gawd!


[intellectually speaking, of course]

 

[DanF]

All valid points. One thing not mentioned, I think, is that it's important to clean the pins on the new socket before fitting. Any greasy (fingerprint) deposits or oxide on the surface of the pins will prevent the solder flowing through the hole. the same applies to the through-hole plating (see the burnt flux (?) remains in one of your earlier photos).

The main connection between the motherboard and the socket is frequently on the opposite side (i.e, the 'top') from where you apply the solder (the 'bottom') and you don't want all the power going through the through-hole plating material. Cleaning the pins will also get the solder to 'take' much more quickly.

Running on battery? Running with battery+charger? Running with charger only? If only when the charger is plugged in, it could be a bad charger (most likely), but it could also be a poor power connection (e.g., supply impedance/board damage introduced by bad soldering ).

If it's always there check cable connections, cable routing and condition of any grounding tape/spring fingers.

The sound issue was a setting on Realtek's software. Recording playback was not muted, so you could actually here every single thing going through the mic, even by touching the case.

 

[DanF]

Did not notice this being mentioned. Just an observation. I would never use aluminum foil as a shield. Just like any other metal it has a very high thermal conductivity so offers very little protection. Not to mention it's electrical conductivity characteristics.

What do you think would be a good alternative? To be honest I did this after watching a video online, and to me looked like a good idea to stop excessive heat transferred to other components.

 

[jbartlett323]

Yeah I'm with Mark, Aluminum foil will transfer heat, not stop it.
I bought some polymide Kapton tape. Its specifically made to stop thermal transfer. Seems to work well, right up until it starts to melt but to be fair, that takes quite a bit of heat... I bought 2 sizes (width's) for different applications. Biggest problem I have with it is that it doesn't stick for crap...

 

[DanF]

Is this the same tape used by laptop manufacturers to organize cables inside?

 

[jbartlett323]

Is this the same tape used by laptop manufacturers to organize cables inside?

In some cases yes. Its the clear-ish, brown-ish tape that wont stick to anything. And god forbid you try to reuse it, cause if it don't stick the first time, it sure wont stick the second!
Mac's use it a lot to prevent thermal transfer on specific chips, its one of their tricks to small form factors. Many other manu's use it for a variety of different application, both because of its thermal properties and durability.