Thinkpads Forum

Hi All,

I have reviewed some old threads on a T400 not turning on. My symptoms are similar, although not identical, so I started a new topic.

Symptoms: System was working fine, opened up lid and computer was completely off. When AC adapter is connected, two lights come on, the charge and the battery, but not the Z indicator. If I remove the battery and keep it plugged in, still no z indicator. If i press the power button, the system turns completely off and all lights go off. There is no HD sound, fan sound, ect. The system does not even start to boot up. Literally no response.

What I have tried so far: I tried static discharge [10x holding power button at 1sec, then 30sec holding it down], tried removing the DIMM and HD and powering up without them. The only thing I haven't tried is disconnecting the backup battery. If i do this, do I try to power it on with the AC adapter while the backup battery is disconnected?

My T400 was bought last September and thus just came off warranty 30 days ago so I am really hoping it isn't the motherboard.

Thanks,
Steve

Try pulling out the CMOS battery and leaving all power sources disconnected overnight. Might work.

thanks! that worked

WOW I would not have thought a CMOS battery would cause a problem like that.

Good call, Colonel