T23 battery doesn't charge, no AC power... smoke?!?!

[doublewong]

One day, while using the laptop (Thinkpad T23) without the battery in it, smoke began to wisp out of the hole where the ac adapter connects. Now it no longer charges the battery or runs on AC power.

(Though does turn on and run on a fully charged battery)

I am not sure if it is a problem with the AC adapter or the part that the AC adapter plugs into. (What is that called?)

If it helps, sticking my computer into a dock/port replicator and plugging the AC adapter to that doesn't charge either or run.

I don't want to start buying random parts till I know whats wrong. How do I check?

Any ideas what might be wrong?

Has this happened to anyone else?

[rkawakami]

Welcome to thinkpads.com!

Sounds like something on the motherboard burned up. The DC jack, what the end of the AC adapter plugs into, probably was not the source of the smoke. Rather one of the electronic components probably gave up its life. A similar thing happened to me a while back:

http://forum.thinkpads.com/viewtopic.ph ... 635#206635

This was with an opened up T23 that I was playing around with. Said motherboard was pulled out and now occupies a place on my desk as a photo model, conversation piece and occasional parts donor.

[doublewong]

The laptop still runs under a fully charged battery, does that change things?

Could it be merely the AC adapter by any chance?

[rkawakami]

It's possible that something burned out on the motherboard which is in-line with the DC power input. That you can still operate the system with just a battery is a little surprising to me. However, say that the main fuse blew and in doing so, let some "magic smoke" out. The power input from the main battery is not associated with that particular fuse (there's another one for the battery) so you could run the system as long as you had a separate way to charge the battery (e.g., external charger). I would normally say that you could check out the AC adapter and rule it out by plugging it into another 16V Thinkpad and see if it works. However, in this case I would caution against it. If, for some reason the adapter is faulty, it might damage another laptop. The best way to check the adapter would be to measure the voltage at the plug and see if it's 16V DC. That would require borrowing/buying a multimeter capable of measuring DC voltages to at least 50V.

[jamiphar]

I had an almost identical problem with my brother's X21. The power jack had been loose for a while and hadn't been working, so he was using it in an ultrabase until I had a chance to fix it. He recently tried the onboard jack again and found that it was now working. So, he kept using it until he noticed some wisps of smoke and the aroma of freshly toasted motherboard.

After a few uses with the AC adapter, the laptop wouldn't work at all without a battery. So I took the motherboard out to resolder the jack, and I found that the loose connection had been causing a short (sparking whenever the AC adapter was in) and it had burnt a little crater into the motherboard. There were exposed and broken traces as a result. I gave up on it when I saw that, so I ordered a new motherboard.

I checked the fuses and tested the AC adapter, and they were all good. I think the loose jack was the only reason it died.