Thinkpads Forum

Since I don't see anyone mentioning this in the X4x forum I figured it is probably not a common problem for the X series.

It started last week. Whenever I plugged in my X41 tablet to the wall by using 16V, 4.5A output AC adapter (FRU: 08K8205) when the battery is in (I always kept the battery inserted on the machine), the power socket sometimes had this high pitch(but not loud, just noticeable) noise. If I removed the battery the noise went away, but it came back when the battery was re-inserted.

To make things worse, the power plug (the terminal of the AC adapter that plugs into the X41 power socket) gets extremely hot after a while. I could not touch the connector (the metal part behind the yellow plastic end) so it is probably over 70C.

My guess is there are probably some capacitors around the power socket is faulty. Before I open it up to check, I just want to see if anyone had the similar experience.

As far as I know X41 tablet was made between 2004 and 2005.

That is definitely not normal.

To rule out the mobo, do you have another AC adapter you can test with? Or a multimeter to test the AC adapter and ensure it is putting out the correct voltage?

I tested the AC adapter. The two adapters I tried on the same machine had the same noise. Then I tested both adapters on my spare X41 tablet and the machine did not make any noises. So I guess it's the motherboard.

After I took the motherboard out of the tablet, I checked the possible cold solder points around the power jack but nothing came up. So I guess instead of mechanical damage over the years of use at the DC jack, it's the electrical component on the board that's causing the problem.

I was hoping it was a simple matter to fix but now I guess I will have to use my spare one until it stops working.

I had a similar problem, very different outcome.
A faulty AC outlet in my home caused a similar issue, strange sizzle, popping sounds. An electrician replaced the outlet and showed me the burn marks on the faulty outlet.
No problem since.

I was searching the forums again for this issue I think I have the very same problem with my X41!

The high pitch noise comes from the yellow DC input plug at the left rear. Initially, wiggling the cord resolved the problem. Over time, it became worse. If the battery were dead for example, the plug would get hot while recharging. All the while, it would be making a somewhat maddening high-pitch noise... to be clear, this is not an arcing sound. It sounds like a stressed high-frequency choke/coil or something like that!

Anyway, eventually, the plug went from only annoying to intermittently functional.

I changed out the AC adapter. No improvement.

I docked the laptop (power via dock with same power brick) and NO MORE NOISE!

Seemingly on to something, I attempted to disassemble the machine. I was not able to easily identify the source of the noise. I had hoped it related to a bad solder joint or something.

So I suppose the clue in my case is no noise when docked. Wish I knew what specifically to replace.

I hope someone else has run into this and found a viable solution??

Sizziling and heat sounds like a short- either the solder is breaking or something is bridging hte contacts. I have a t41, and I know that the plug is connected with a cable to the motherboard. I also have a dissasembled 390e (need to post about that), where the socket is mounted to the motherboard. If the socket was loose, or something (staple...) dropped in and shorted, that sounds like the symptoms. Especially since it works in the dock. Good luck.

I'll have to record and post the noise.

It seems like it is something north of the power connector itself. It isn't anything like an arcing sound and there are no signs of arcing or burning on the plug or socket. The center insulator on one of my power bricks did get warm enough to melt a bit though - not good!

If I were not so dependent upon this laptop, it would be much easier to t-shoot!

One thing I can suggest is possible flexing of a solder joint. I know that if something is only partially contacting, heat and sizzling noises can be common. Now, I have heard that DC voltage doesn't produce these problems but I have a hard time believing that. I have seen DC voltage arc.

I'd be looking for signs of discoloration or scorching. I have read through the post and realize that this may not be the problem, but it's worth mentioning.

Take the battery out, then use a hooked/bent paperclip to lift/bend up the halfmoon-shaped (earth) contact inside the DC plug.
This is probably only making a halfhearted attempt at contact.
Worst case scenario, replace the DC connector.

Brian10161 wrote:One thing I can suggest is possible flexing of a solder joint. I know that if something is only partially contacting, heat and sizzling noises can be common. Now, I have heard that DC voltage doesn't produce these problems but I have a hard time believing that. I have seen DC voltage arc.

I read somewhere (not sure), that some laptop adapters are actually too high current for true dc, and are in fact ac currents that appear to be dc (no idea, this may be wrong), but I know that that would explain the popping noise. I have also seen dc currents arc.

Good luck

I finally recorded this. The sound recorder that comes with Windows 7 is the most pitiful thing I have ever seen. Wound up with a free copy of "Audacity", a nice little sound editing program...

I could not find a way to upload so placed a copy on one of my severs...
http://64.69.122.170/x41powerIssue.mp3

The sound in real life is just as bad as the recording!

Thanks for all the ideas by the way. I now wonder if there is some AC over the DC. That sure seems possible? I have tried 3 different IBM power packs with the exact same result though.

Thanks!

Sounds like somebody blowing up those giant birthday balloons.

Kazoo solo

Sounds like a very loose solder joint, where the current is breaking and reconnecting to fast to make a popping sound.

Jack

I have this exact same whining problem on my X40. It's coming from the laptop, not the AC adapter. Did you ever get it fixed?

I see eBay has several X40 motherboards for sale. Would that take care of it?

Dear Everybody,

To make things worse, the power plug (the terminal of the AC adapter that plugs into the X41 power socket) gets extremely hot after a while. I could not touch the connector (the metal part behind the yellow plastic end) so it is probably over 70C.

I had exactly this problem and, finally, I solved it for my X41t type 1866.
(In addition, with a dc connector plugged in, a battery could not be loaded.)


The problem was a broken soldering joint on the pcb. Just remove your keyboard and locate the dc connector on the pcb. The inner contact's (positive potential) soldering joint is reachable from this side.
This problem is similiar to this [0].

Now the connector's tip stays colder than 70C and my battery is loading again ....
[0] "PROBLEM: X41 läßt sich nicht einschalten, keine Anzeige der Ladekontrolleuchte - auch nicht über Dockingstation-Ladebuchse ... (PANIK) " http://thinkwiki.de/X41

Exactly the same symptoms since half a year, bought a new battery - to no different effect.

On dissassembling I found slight browning of the board around the connector and the mains-pin to the board (from the pwr-jack) black (accumulated heated dust). That points to a bad connection, which in turn figures with the rest of the symptoms. The only cure I see at this time is to take the board out, remove the pwr-connector and get in in shape (de-oxidize, stronger pressure) or insert a new one (I found them offered in GB about 2,5, Ebay).

Try to wiggle on the connector-jack, when the hissing occurs. With me I found that the symptoms were gone for a short time occasionally. That obviously points to a bad connection somewhere, which might be on the board as well as within the connector, as its contacts could oxidize with age. In both cases resistance can rise and at this point the amps will generate heat instead charging the battery.

I hope my guesses are correct, as I want to keep that thing, I ll be back.

It is fixed. Problem is a assembling flaw of the pwr-socket, as the +terminal should not get hot enough to solder properly.

Anyway:
to fix this you will have to take out the systemboard completely (using the hardwaremanual it is easier as it seems to be, nevertheless you need some screwdrivers), remove (desolder) the connector and clean it resp. get a new one. As I do not know the layout of the board I recommend on both sides to scratch away the paint on the copper around the soldering point, insert the connector and solder it - make shure, the solder is smoothly flowing ON THE PIN, as this is a heatsink compared to the board.

Thats all, first time so took me ap. 3 hours alltogether (however, I have the tools, de-soldering is quiete challanging because of tight space as well as the thin board and bending forces on it removing the connector). All batteries now back to 100% like out of the box, bottom not even lukewarm.

What a relief - I got used to that one. By the way:

I found my sound detoriating to the point not to be heard. On dissasambling I found, that the speaker (magnet!) was partly covered with iron-dust (as I take it next to the bench sometimes). Removing that (brush, air) it now works again - there should be a protector like some silk behind the grille.

All now

I got a few pics about that, but dont know how to upload them here.

The forum has no option for that.
Put those pictures on e.g. imgur.com, or Google's Picasa, Inkfrog, Imageshack, etc.
Then just post the links to them.

Thanks, I did, you will find them
https://imageshack.com/a/fRSb/1

x41 merely indicates some abnormality like the discoloring, giving a hint as to where precisely

x41(1) needs a close up, it will show a crater of tin around the pin making this spot most probable

(2) the disassembled connecto - take care to look INTO it, as the "end" of the pin shown is far bigger, it is a mass "functioning like a heatpipe

(3) take note of the narrow ring for soldering, it will not hold enough tin on machine soldering to heat the pin up enough, my guess is, that the fluid solder will contact the pin, heat being drawn will make a cold spot not combining with the surface,

(4) preperation for the soldering (both sides)

(5) as it should look like on the PIN! (heat sink!)

It's all in the solder you use!
My favorite is this Stannol Lux II, P/N 637463: http://plussystem.de/shop/article_01-63 ... -637463%26
Since you are in Germany, you should have no problem getting it.
And never mind the (lucky lack of) stupid RoHS compliance!