Thinkpads Forum

Hello, my problem is that recently my TP T21 has refused to start sometimes when i press the power on button. Not always though; sometimes it works at the first go, sometimes it won't start after a hundred tries at the button (figuratively speaking). When there is a starting problem, the effect of pressing the button is that the hard disk light and thebattery light flash for a split second (i never use the battery, and it's not attached), but nothing more happens.

I'm not quite sure what the problem is, but anyway if the TP does start, then there is no problems, i.e. no unwanted power-offs or anything, so probably it has something to do with the switch-on phase.

Searching this forum (it might have been elsewhere too) i found a message where someone hinted at the possibility that the starting voltage provided by the adapter is too low, and hence the computer does not start

I don't know how computers might operate in this respect.. i'm an electrician, but not specialised in electronics

My adapter's nominal values are 16VDC and 4,5A (with 230V on the primary side), and measuring the voltage with a multimeter i got 16.75VDC which seems ok.. any ideas of what is going on? As i mentioned in the beginning, this problem has appeared only about a week ago, apparently for no special reason.. one evening i switched off the computer, and it sat on the table until next morning, when it refused to start.

Joonas Laine

Change the CMOS battery. It's a small, yellow shrink-wrapped lithium watch type cell underneath the main battery.

Please put your location (at least SF) in your profile.

Regards,

James

Hello James,

I tried changing the CMOS battery, but it did not help.. (and the BIOS never popped up anyway before I actually removed the battery in order to change it). Afterwards I took my TP to a repair guy, and he suspected maybe there's an overheating problem (but said that it doesn't really pay to invest any money in a computer like this.. mine is rather worn and probably has 50€ resale value :).

As to overheating, though, I'm not so sure, as it doesn't switch on even when it's been off and unplugged for the night.

Any other ideas?

It might be the switch for the display lid. Does your problem happen after the display lid has been closed? If it won't start, try pressing and releasing the little button the display lid depresses when you close it, then press the power button again.