My notebook won't turn on?

Question

Compaq Presario 2100US. My note book will not turn on. I press the power button and the lights come on like it is trying to boot up but then it shuts down 1 second later. A light on the front of the computer shows it is getting power. My power supply is supposed to be 19 volts and 4.0 amps. I hooked it up to a multimeter and it showed 19 volts. It was swinging back and forth between .5 and 3.0 amps. I replace the power supply and it will still not turn on. I have tried resetting the BIOS by keeping the power button pressed. I have tried booting it up without the battery. I have hit the reset button on the bottom of the unit. None of these things seem to work. The battery has a little meter on the side that shows it's amount of charge. It shows zero. What could be the problem if it is not the battery?

Answer 1

I've had this problem appear from several different laptops. Your battery and power appear to be working fine. Oddly enough, and even though it sounds unrelated, what usually fixes it is to reseat the hard drive. Open up the user access panel on the bottom of the laptop and remove the hard drive. Dust it off if necessary then reinstall it making sure the drive is seated tight and snug onto the drive connector. Reinstall the access panel and screw in snugly and restart your machine.

Give it a try... good luck!

Answer 2

Some laptops require a good battery to be installed before booting. You might try removing the battery and attempt starting the computer from just the AC adapter. If that doesn't work, I'd try to get another battery that is known good. If that fails to work, your power supply board is likely blow or getting intermittent contact inside the laptop. You could open it up and try looking for cold solder joints in the ac adapter connector and in any power transistors on that board. If none of this works, I'd suspect you have a fried northbridge or CPU. Hope this helps!