how to test power button when it is on keyboard

[koby058]

Hi

Is there a generic way to test power button voltage or to power on a laptop without schematics when power button is on keyboard ?

Thanks

[keeney123]

Re: how to test power button when it is on keyboard

Hi

Is there a generic way to test power button voltage or to power on a laptop without schematics when power button is on keyboard ?

Thanks

I guess that would be dependent of the Manufacturer and the model of the laptop. Of course, one could press the power button and if the unit did not turn on then one could assume a problem. It would be near impossible to diagnose a dead laptop without opening it because most connectors on the outside of the laptop are outputs. Even if one used a connector that has the ability to also input data, the unit would need to be up and running. I am sure if the keyboard could be removed there are testers that can power up the keyboard and test the keys if the unit is not running. Otherwise, one would have to determine if the power key is just a switch to power the unit on or if there is some type of strobe pattern that is going to the power key that another component is looking for then start up a power up sequence.

[reformatt]

Re: how to test power button when it is on keyboard

Power buttons on keyboards can be metered usually at the last two pins of the keyboard connector, at least this is what I've found so far. One of the two will be ground of course, determine that with your meter. The other should be pulled up to 3.3V, and go low when power button is pressed. You can short these two pins with tweezers of course to see if lappie fires up. Had plenty of Acers with bad power buttons on the keyboards, and the tweezer method just confirms it. Also had plenty where the button is always triggering too, resulting in the laptop switching off randomly.