AC adapter jack problem on laptop

Acer / EXTENSA 501DX
March 19, 2009 at 13:00:09
Specs: Win98SE/Mepis 2004, Intel Pentium MMX 266 MHz
The old Acer Extensa 501DX has been doing this ever since I got it. I have tried Googling the problem, but I found pretty much nothing, so i'll try here.

This problem has been getting worse and worse - When the AC adapter is plugged into the laptop, you have to continually wiggle the plug (on the laptop end) until the battery charging light comes on and the laptop will power on.

Not only that, but once the laptop is on, the slightest movement of the AC adapter plug (usually by bumping the cord, moving the laptop, etc.) causes the plug and the jack to lose contact, and the laptop shuts off. (The battery does not hold a charge.)

Sometimes you don't even have to move it - after the laptop has been running a little while and the plug gets warm, it can loose contact and shut it off.

Although I didn't find any information on the problem or any solutions, what I did find in the Google search is that this problem is common with the Acer Extensa 500 series, and it's rebranded counterpart, the IBM ThinkPad i14xx series.

I think (aka, I hope) it's something simple like the motherboard soldering for the AC adapter jack has broken off, and I can re-solder it myself.

I do have the service manual that shows step-by-step on how to completely dissasemble the laptop. (Which you need to do to get to the back of the motherboard.) I want any suggestions from the folks here before I go about doing that, though.

Oh yeah, I have tried different 12V DC plugs. Same thing.

If anyone knows about this problem, or has even a faint idea about it, thanks in advance for the help.

-Trent

"If at first you don't succeed, skydiving may not be for you."

-Our tour guide at Fenway Park in Boston, MA.


See More: AC adapter jack problem on laptop

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#1
March 19, 2009 at 13:07:07
It's pretty common for the adapter Jack to break loose from the motherboard due to the plugging and unplugging of the adapter (poor design).
Remove the cord and reach in with a finger and see if it's loose.
It might just need a re-soldering job.

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#2
March 19, 2009 at 14:02:54
"It's pretty common for the adapter Jack to break loose from the motherboard due to the plugging and unplugging of the adapter (poor design)."

It's more likely caused from people pulling on the cord instead of the plug too often, or pulling it out at an angle, not poor design.

If you're going to take apart the laptop anyway, you might as well get a new replacement jack off the web. The existing jack may not work properly even after you re-solder it.
You'll probably need a solder sucker as well as a soldering iron.


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#3
March 19, 2009 at 14:06:49
It's an irritating problem; I'd go for it.

Either resolder the jack or replace it if you can find one.

Pay close attention to the different sizes of screws and follow disassembly/assembly instructions to the letter. Use good tools, this is not the time to use dollar store drivers.

Skip


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Related Solutions

#4
March 19, 2009 at 14:13:31
Tubesand wires, I think it was poor design to depend upon the solder joints to hold the jack. It would have been much wiser to fasten the jack to the case and connect the jack to the motherboard with flexible wires.

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#5
March 19, 2009 at 15:00:23
'It would have been much wiser to fasten the jack to the case and connect the jack to the motherboard with flexible wires"

That's certainly true, but people who pull the plug and pull it straight out like they're supposed to don't have the problem.
That's a very common stupid thing people do - pull on the cord rather than the plug, for whatever cord.
Even if it were not soldered to the mboard, people who pull on the cord would damage the jack.
You can't protect everything from stupidity. It takes a LOT of abuse for the jack to get to the point it's detached from the mboard.

A simple thing they could do that would help a lot would be if they stopped supplying AC adapters with plugs that are at 90 degrees to the cord - it's those ones that are more likely to damage the jack when you pull on the cord.



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#6
March 19, 2009 at 16:08:24
Whew, I wasn't expecting this much so soon! Thanks for the replies!

"Remove the cord and reach in with a finger and see if it's loose. It might just need a re-soldering job."

It's very loose. Wiggles around about half an inch in all directions.

"It's more likely caused from people pulling on the cord instead of the plug too often, or pulling it out at an angle..."

It was used in a (my) school, and then as a game computer for my Math teacher's small children. Who knows what it might have gone through! This laptop looks like it's never seen a kid, though.

"...you might as well get a new replacement jack off the web. The existing jack may not work properly even after you re-solder it.
You'll probably need a solder sucker as well as a soldering iron."

You're exactly right.

"Pay close attention to the different sizes of screws and follow disassembly/assembly instructions to the letter. Use good tools, this is not the time to use dollar store drivers."

You got it. I don't know how "good" my screwdrivers are, though. They've never failed me before! lol!

"That's a very common stupid thing people do - pull on the cord rather than the plug, for whatever cord."

I hate it when I see people do that to their electronics. I am always careful with pulling plugs out, though.

"A simple thing they could do that would help a lot would be if they stopped supplying AC adapters with plugs that are at 90 degrees to the cord."

That's what this one is. I never thought about the 90* plugs posing problems, before.

Luckily, this laptop just uses a generic type of AC adapter jack that is found in 99% of electronics, so they should be cheap and plentiful to find.

I'm going to be pretty busy this weekend (much homework from school), so i'll get to it when I get some free time.

Thank you for the replies,
-Trent

"If at first you don't succeed, skydiving may not be for you."

-Our tour guide at Fenway Park in Boston, MA.


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#7
March 20, 2009 at 10:12:46
"It's very loose. Wiggles around about half an inch in all directions."

If you're not greatly eggadurating (sp?) , then in that case it's probably not attached to the mboard and never was.

"Luckily, this laptop just uses a generic type of AC adapter jack that is found in 99% of electronics, so they should be cheap and plentiful to find."

They're often NOT like the generic ones used in other things on laptops - if they were generic there wouldn't be so many listings for them on the web - but if yours is not soldered to the mboard it MIGHT be.
Search on the web and find one that is specified for your model. The ones that solder onto the mboard usually have extra metal tabs on them to anchor them to the mboard more securely


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#8
March 20, 2009 at 14:03:22
Exaggerating. :)

I always think that inches are smaller than they are. I took a look at a ruler. I would say it wiggles about 1/4" around. Maybe 1/5".

I don't think generic is the right word for it, but I do know that it is the same type of round jack that is used in many other electronic devices, because just about every other AC adapter I have fits into the jack perfectly.

I did a search for "Acer Extensa 500 AC adapter jack" and "IBM ThinkPad i1410 AC adapter jack" and got nothing but AC adapters themselves.

What is the actual name of the jack? Maybe that would help.

-Trent

"If at first you don't succeed, skydiving may not be for you."

-Our tour guide at Fenway Park in Boston, MA.


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#9
March 21, 2009 at 11:51:21
Don't use the quotes to enclose the entire search string.
Don't use adapter - the jack isn't on the adapter - or power.
e.g.
Acer Extensa 500 dc jack
or
"Acer Extensa" 500 dc jack
produces suitable "hits"

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#10
March 22, 2009 at 09:41:35
I didn't use quotes in the search string. I used quotes here to show you what I typed.

Tried your two examples, as well as replacing Acer Extensa 500 with IBM Thinkpad i1410. No go.

-Trent

"If at first you don't succeed, skydiving may not be for you."

-Our tour guide at Fenway Park in Boston, MA.


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#11
March 22, 2009 at 19:38:36
I use Yahoo.
Those suggestions I made work fine in that.

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#12
March 23, 2009 at 07:00:47
i have recently repaired two of these for friends. the centre pin on the socket was loose and had broken away from motherboard. on both of these i resoldered the centre pin but also for good measure added flexible wires. So even if the solder connection gets broken again the current should still connect throught the wires.
It is not a good design, particularly if power socket is at back and there are memory card sockets on front edge because people tilt the laptop up to see where they are putting the card in the front slot, thus putting a lot of strain on the power connector at back.

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#13
May 3, 2009 at 18:15:20
Well, I summoned my courage and disassembled the whole laptop. (Required to get to the AC adapter jack.)

The situation is perfectly fixable - the jack itself is in perfect condition. Two metal strips (each about 0.75" long) travel from the jack, and the ends of those strips are soldered onto two small, metal-ringed holes on the mobo - the soldering on one of those metal strips broke, so the metal strip could move freely, but because it was long enough to poke through and stay in the metal-ringed hole, it could only intermittently touch the metal lining, hence my problem.

All I need is a soldering tool for small jewelery. Cheap as I am (lol), i'll borrow one off of a friend or family member.

I made a shocking discovery while scanning the underside of the mobo - sometime during this laptop's life, one of the various black, processor-type things - a small one - severly overheated (more likely, shorted out) and caught fire! It's just a melted ball of ceramic and metal, and all of the motherboard surrounding the "processor" up to about half an inch away is charred black.

What i'm concered about is, I can recall 2 or 3 times in the past when I was using this laptop, and the surface where that part of the motherboard is got so hot that I could't even touch it! If I get the AC adapter jack fixed, i'm not leaving that laptop turned on during the night! It apparently didn't hurt anything, because everything functions perfectly (except the AC adapter jack) on that laptop.

-Trent

"If at first you don't succeed, skydiving may not be for you."

-Our tour guide at Fenway Park in Boston, MA.


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#14
May 5, 2009 at 07:53:42
"....the soldering on one of those metal strips broke, so the metal strip could move freely..."

may be directly related to...

"....one of the various black, processor-type things - a small one - severly overheated...."

I don't know what you mean by "... processor-type things...".

If "It's just a melted ball of ceramic and metal..." how do you know what it was?

There aren't all that many things that would cause that much damage, assuming it wasn't caused by a sparking connection from the loose connection to the power adapter jack.
E.g. a voltage regulator - check the current mboard voltages in your bios settings

"It apparently didn't hurt anything, because everything functions perfectly"

Are you sure? Do you use all the functions of the laptop?
Are there some ports or slots you don't use?

"If I get the AC adapter jack fixed, i'm not leaving that laptop turned on during the night!"

Your ATX mboard is always powered in some places even when it's not running, as long as the mboard battery is installed. You would need to remove the mboard battery as well.


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#15
May 5, 2009 at 12:23:42
"....the soldering on one of those metal strips broke, so the metal strip could move freely..."

may be directly related to...

"....one of the various black, processor-type things - a small one - severly overheated...."

They are on opposite sides of the mobo, but I know what you mean. As a matter of fact, sometimes when I had the battery (which is no good) connected, the AC adapter plug would get very hot itself. Could be related...

I don't know what you mean by "... processor-type things...".

You know, the flat square black things of various sizes that are placed all over the motherboard. They look like a processor, except they have no heatsink (except for integrated GPUs) or fan, and most are smaller than a processor. The northbridge and southbridge are usually the biggest ones, and the USB and sound chipsets are the smallest.

If "It's just a melted ball of ceramic and metal..." how do you know what it was?

The outside of it was spared from melting, and it was a square shape.

...check the current mboard voltages in your bios settings

Nothing in the BIOS at all, just pages to change very basic settings. Unless there is some key combo you're supposed to press to access hidden pages for more advanced features.

Do you use all the functions of the laptop? Are there some ports or slots you don't use?

I've never used the 56k modem, parallel port, serial port, or port replicator, but I don't care if those work or not, anyway.

Your ATX mboard is always powered in some places even when it's not running, as long as the mboard battery is installed. You would need to remove the mboard battery as well.

The surface of the laptop by the melted part and the AC adapter plug never got hot unless it was trying to charge to battery, and in very rare cases when the battery was out. I don't bother putting the battery in anymore, though, and it doesn't get hot anymore, so it's probably safe.

-Trent

"If at first you don't succeed, skydiving may not be for you."

-Our tour guide at Fenway Park in Boston, MA.


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#16
May 6, 2009 at 07:50:57
"You know, the flat square black things of various sizes that are placed all over the motherboard. They look like a processor, except they have no heatsink (except for integrated GPUs) or fan, and most are smaller than a processor. The northbridge and southbridge are usually the biggest ones, and the USB and sound chipsets are the smallest."

That's a rather vague description. Components that are flat and square or rectangular can be many different things. e.g. If they have only two connections they can be a resistor, a non-electrolytic capacitor, a diode, etc. If they have three connections they can be a voltage regulator, in which case they sometimes have a tiny metal portion to disappate heat and are bolted to the mboard, or are soldered on their back to a obvious larger area of circuit trace, or a mosfet, etc. If they have more connections than that, those are usually ICs - integrated circuits - true "chips".
Most main chipsets have two main ICs - chips - the northbridge and southbridge - some older main chipsets also have one or more essential additional chips connected to those chips thgat are required for the main chipset.
There is always also another essential IC - the I/O chip.

The only thing on a mboard that is an actual processor is the cpu itself, whether it is in a socket, or soldered into the mboard which is sometimes the case with older laptop mboards, and a few desktop ones.
......

Old laptop main batteries are bad news. Laptop main batteries only work as they were designed to for about a year, then they begin to deteriorate. After a couple of years they can no longer be charged to anywhere near their full capacity, and they have a tendancy to short internally when they are older, especially NiCad ones, and that could certainly cause overheating of circuits when you try to charge them.


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#17
May 6, 2009 at 15:34:27
The melted part must be an IC then, it has about 20 connections.

It looks like this, except melted in the center:

http://virlab.virginia.edu/VL/Semic...

I'm curious as to what it's (or what it was) for...

...and they have a tendancy to short internally when they are older, especially NiCad ones, and that could certainly cause overheating of circuits when you try to charge them.

It's the original battery from 1999, and it's NiCad, so that's most likely what happened. Amazingly, I could get almost 15 minutes of run time out of it at times.

-Trent

"If at first you don't succeed, skydiving may not be for you."

-Our tour guide at Fenway Park in Boston, MA.


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