T 23 will only start up on battery

[Lars]

Hi guys,

My trusty T 23 has developed some bad habits lately. Since a couple
of months it will abort startup after some 10 seconds or so when
plugged in. It does post, goes through boot menu, and initiate start
of Windows, then it just switches itself off.

But as soon as I unplug the AC it will start up just fine on battery. And
once it is up and running I can plug in the AC again, and everything is
fine for hours.

I suspected memory problems, but after running extensive tests on
the chips I have found no problems with those.

What could this behaviour indicate?

[RealBlackStuff]

Try borrowing another AC-adapter.
Does that adapter stay plugged into the mains and hooked up to your T23 even when the T23 is OFF?
Does the adapter get hot?
If you push on the plugged-in connector at the rear of the laptop while starting up, does that work?
Is your power jack in the T23 OK?
Does it start on AC with the battery removed?

[Lars]

Try borrowing another AC-adapter.

I have several myself. There is no difference in which one I use.

>>Does that adapter stay plugged into the mains and hooked up to your T23 even when the T23 is OFF?

Normally yes, but not always. At times I take it back and forth to
work and it may be left in my bag.

>>Does the adapter get hot?

No, just warm.

>>If you push on the plugged-in connector at the rear of the laptop while starting up, does that work?

Have not tried that yet, but since I have several adaptors ....

>>Is your power jack in the T23 OK?

I think so. After all it works fine once it is past the startup.

>>Does it start on AC with the battery removed?

No. That is how I have normally run it for several years. So when
it first started acting up I thought there was a memory problem.
Only by chance did I realize that it actually started up fine on battery.

[RealBlackStuff]

Check the big rectangular inductor left of the CPU. It may need resoldering.
While you're at it, check all the other (square) inductors as well.
You'll need to take the mobo out to get to the (important) ones on the bottom.
Wiggle them all to see if any are (coming) loose.
If/when you replace or resolder an inductor, they can go in either way, there's no polarity.

[truk]

I think you may be going at this the wrong way. It sound like Windows is terminating and shutting down when it tries to boot on AC. It may be a fault with the powermanager. To see if this is a problem, try booting off a CD. If it boots you can probably blame windows, otherwise it's hardware.