T23 won't boot/power after shutting down (new mobo!) PIC

[BDMK]

i've had this ongoing problem with my T23.

last month, suddenly it wouldn't boot/power at all after being normally shut down.

took it to repair-they told me it's either a loose cable/connector tied to the power button or the whole motherboard needs to be replaced. they tried fixing the former issue first-they told me they tightened up all the connectors inside.

took it back home, it worked for a week. then, again, it wouldn't power back on suddenly. back at the repair place, this time they replaced the whole motherboard.

took it back home just this friday, worked for a day. then, again, it won't power back on yesterday, now with a new motherboard in.

now what? any suggestions are appreciated.

Admin note: Added PIC warning

[RealBlackStuff]

Welcome to the forum.
Could you have a dud power supply?
Or a bad battery?
Does it work on either AC alone or Battery alone?

[BDMK]

hi RBS,

does not power at all-neither on AC nor on battery alone. (light goes on when AC is plugged in telling me power supply/battery charging is working)

[rkawakami]

If the MiniPCI card was transferred from the old motherboard onto the new, then it might be the problem. Pull it out and see if the system can power up. Alternately, you could be looking at loose inductor(s) on the board but that means both your old one and new motherboard suffer(ed) from the same problem.

[BDMK]

hi ray,

the repair guy did mention 'loose' parts in the mobo the first time he worked on it.

now, if this is a recurring issue, does it mean i just have rotten luck (both old and new mobo just happen to have loose inductors) or is this a known issue? and if this is the case, can anything be done to fix this or do i just keep going thru mobos?

[rkawakami]

Known issue. During the time when the T23 motherboards were being assembled, I believe that the electronics industry was switching over to the first formulas of lead-free solder. That, and along with some flexing of the chassis, or contamination of the inductor leads, or poor application of the solder paste, can cause the inductors to pop loose from the motherboard. There's at least four of them that will give you trouble; one just above the CPU, another near the battery terminals (both on the top side of the motherboard); two on the bottom of the board just opposite the PCMCIA slots. These are the usual indications that you have loose inductors:

- system totally dead: the one next to the CPU
- lack of battery charging: the one next to the battery terminals
- system turns on but the fan acts strange: the two on the bottom
- intermittent power issues, especially noticeable when flexing the system by the front corners: CPU or bottom inductors

To fix them requires cleaning the pads of the inductors (which will usually have some black or gray oxidation) and where they are mounted on the motherboard. Using leaded solder to re-attach them also helps. Also, once the board has been repaired, don't pick up the laptop by just one corner; use both hands to lift up/support the system. But try the MinPCI card first; it doesn't require taking the system apart .

[BDMK]

followup questions: could this be solved if we install an unused t23 motherboard? also, does it have to be a t23 motherboard or can it be a t22/21/20? lastly, do you know of anyone on these boards who might have a 'new'/not-before-used t23(compatible) motherboard and willing to sell it to me?

p.s.: we looked at the motherboard we removed from the t23 and the inductor close to the CPU seemed in fine shape (no oxidation/not blown out/etc), further stumping us...

EDIT: ray, i just noticed (forgive me, i'm still a newbie here) that you had posted a detailed scan of a t23 motherboard on the forum. could you be so kind to point out to me on that grid exactly which inductor you were referring to as being 'next to the CPU' just to make sure we were/are looking at the right one, and post the link to the scan here again? much appreciated when you got a free second...

[RealBlackStuff]

The big rectangular one near the CPU is missing on the picture, but sits at
A1/A2 on http://www.rkawakami.net/ibm_t2x/mobo_top_72_legend.jpg
The not-charging (gray square blob) is located at G6

The ones that cause a pulsing fan (gray square blob) are at D9 and E8
on http://www.rkawakami.net/ibm_t2x/mobo_b ... legend.jpg

On your own mobo, wiggle those blobs. They may well come off. When you solder them back on, there is no polarity, either way is fine.

[rkawakami]

Thanks for covering for me RBS! (Man, having a regular job sure sucks time away from this forum...)

[RealBlackStuff]

followup questions: could this be solved if we install an unused t23 motherboard? also, does it have to be a t23 motherboard or can it be a t22/21/20? lastly, do you know of anyone on these boards who might have a 'new'/not-before-used t23(compatible) motherboard and willing to sell it to me?

Your problem may be solved by installing another mobo, not necessarily a new one.
And it's got to be a T23 mobo. None of the others will even fit.
Put in a want-to-buy or WTB ad in our Market forum or check eBay for T23 mobos. There are 2 P/Ns and FRUs. Either one will do fine.

[Robbyrobot]

Is there such a thing as a new T23 motherboard - unless someone bought one when the machines were still being made and hoarded it all this time

At any rate, I'd go along with the consensus that the best thing would be to resolder the inductors. I've also made a scan of those on the top and bottom of the board:

Top Bottom

Ray, could you please change the subject to reflect the thumbnails?

[kurtista]

i don't know if this will do it for you, sounds like it might be a little more complicated in your case... but my t23 did the same thing and i found a trick that has worked at least 2 times for me. what you do is take out the battery(not the cmos, leave that one in) also make sure to have the a/c adapter disconnected. open up the lid and hold down the power button down for 30-45 seconds. then put the battery back in, and connect the power cord. hopefully you'll be good to go!

[BDMK]

UPDATE:

the specific inductors on the mobo weren't loose/discolored at all. do we still detach and resolder them?

[rkawakami]

No, I wouldn't mess with them if they are still firmly attached to the board. You can test for holdfastness (?) by sliding a toothpick underneath one corner of the inductor and gently try to pry it up. All of the ones which were a problem for me failed this test drastically (watch out for flying inductors!). There's a certain trick to getting them resoldered back on the board so, "if it ain't broke, don't fix it".

The main fuses and DC power jack should be okay since you said that the system appears to be charging the battery. Main fuse protecting the DC power jack is at map location A5 and is marked F2 (clear looking rectangular chip with FU printed on top). The one protecting the battery is at G6 and is labeled F12 (silver endcaps and white body).

Another possible problem area would be the power switch on the keyboard. About the only way to figure out if that's the issue would be to replace it with another keyboard which is known to be good. Alternately, if you have a docking station/port replicator that the T23 fits into, then you can try using the power switch on the dock/replicator and see if that gets your system to power up.

Otherwise, while you have the system apart, it wouldn't hurt to re-seat the CPU (turn the screw cam counter-clockwise 180 degrees, make sure that the CPU is resting firmly down on the socket and then turn the screw clockwise 180). During re-assembly, leave out the MiniPCI card, ethernet card, hard drive and memory. Power up. You should get the 1-3-3-1 beep code for bad (or missing) memory. If it doesn't power up, then I'm afraid that the motherboard is kaput.

ref: http://www.rkawakami.net/ibm_t2x/mobo_top_72_legend.jpg (T23 motherboard - top side)

[BDMK]

just want to let you know: it WAS the keyboard, after all.

now the PC is back to normal.

thx everyone for being so helpful. this is a great forum for all of us thinkpad fans.

[RealBlackStuff]

Thanks for letting us know. Enjoy your T23.
KB failure is quite rare, even of old(er) KBs.