T21 Won't boot

[bossman74]

I'm working on a friend's Thinkpad T21

He's having an intermitent problem with it and I can't find the cause or solution.

It sometimes doesn't boot, when I press the "power button", the hardisk led flashes once and nothing else happens. I've tried taking it appart, and reseating all connections, hardware and cables. It then start without any problem but after a few hours, if I shut off, I get the same problem again.

The battery is not holding a charge, but that shouldn't be the cause when the AC adapter is plugged in right ?

As anyone experienced this before, and do you know how to fix it ?

[JHEM]

First step in these cases is to replace the CMOS battery.

Report back.

Regards,

James

[Orevin]

This is a common problem and was discussed many times on this board. Here is a thread that includes pretty much all things to check: http://forum.thinkpads.com/viewtopic.php?t=21812

[bossman74]

First step in these cases is to replace the CMOS battery.

Report back.

Regards,

James

I changed it and that did not do it.

What else could it be

[Hard_8eight]

Check my notes in T21 Battery/AC Power issue posted dated 06/29/06. The steps I took worked for me.