Hi,
My ThinkPad T42 laptop just went dead for no apprent reason and now it won't power on at all, not even the power status light is coming on.

I was doing some work on it then left it on for about 15 mins, when I came back I found it off and it's been that way since. I have had the power pack checked and it's working fine.

Can any one help?

Thanks

A bad battery or charging circuit may be attempting to pull too much current. Remove all batteries and see what happens. In fact, remove all removable devices (drives, mouse, PC Cards, USB, etc.) - just to eliminate them from the equation.

If batteries, charging circuit and the DC power supply is good, then this is usually caused by a broken or worn power connector in the notebook, or a "thermistor" or "fusible link" inside the notebook that blew, for some reason. The "for some reason" is the tricky part. Thermistors and fusible links are circuit breaker type safety devices designed to sacrifice themselves by burning up, thus "opening" the circuits they are protecting from abnormal power (high-current) conditions.

Visually inspect the notebook's power connector under a bright light to see if damaged. If you are certain there is no visible damage (bent pins, signs of smoke or excessive heat, cracked plastic, etc.) connect the power pack and gently wiggle around the plug to see if connection is made - strategic positioning of tongue is often necessary.

If a fusible link blew, the tricky part is determining why did it blow? Did it fail prematurely on it's own? They do - they are not very high-tech or expensive. Was it just a fluke? Gremlins? Can the link be replaced and everything will be okay? Or is there something else wrong in the notebook, a short somewhere that is causing too big of a current flow in the circuit? If the safety device blew because it overheated due to too much current draw through the circuit, then replacing the link will simply result in the new link blowing, hopefully before further damage elsewhere occurs.

In either case, if it is the connector, or something else internal to the notebook, it will need to go into a good shop. Replacing power connectors and thermistors/fusible links is a relatively simple task for a qualified repair person - disassembly to access the parts and re-assembly takes longer than actually removing and soldering in new components. The parts, are inexpensive and should not take more than one hour of labor.

However, if the fusible-link failed "as designed" because something else failed, then troubleshooting may take some time and replacement parts may be expensive. You may have to decide between fixing or replacing the entire notebook.

If it is under warranty, call it in.

In the meantime, you can get a Notebook to IDE Hard Drive Adapter and temporarily attach your hard drive to another computer to copy off your personal data.

Thanks for the feedback, I'll take a closer look at it and see what I can "see!"

Hi I tried most of the suggestions given without much joy, so I'm beginning to think it's probably the mainboard or CPU, so I'll just leave it and use the laptop as a door stop. Thanks y'all.