Laptop Lid Switch Location?

[chris301up]

Does anyone know where the on/off switch if located on my laptop? Have changed the wireless antenna recently and the unit no longer switches off when I close the lid. Any help would be greatly aprecaited

[erico]

Lid switches, actual physical display lid switches are a thing of the past with smaller laptops. I have not seen one in perhaps fifteen years except in large laptops.

The technology to turn off the display has moved on to hall sensors activated by a magnet.

You can find where the hall sensor is by using a small magnet while the laptop is on, but only if the hall sensor board is still connected.

Your description sounds as if you disturbed or displaced the hall sensor board in the base enclosure that is there to activate the hall sensor which turns off the display. Perhaps you left the board connector disconnected.

[chris301up]

Thank you for your reply and sorry for not responding sooner. Have checked everywhere for a hall sensor board, but cannot locate it anywhere. I have used a magnet, with the lid open and closed as much as possible, but nothing. I have just removed the screen to check if I disturbed anything there, but all seems fine. I will reassemble shortly and see what happens. The 'good old days' of switches was far the best 😂

[chris301up]

Cables routed above hingeCables routed under hinge

Right, I think more by luck than judgement, I have stumbled upon the answer to my problem. Whilst working on the laptop I noticed the cables from the screen and wireless antenna were initially routed above the hinge. As an experiment I thought I'd try routing the cables underneath the hinge. See photos. Now the screen switches off when closing the lid. I cannot see any logical reason for this but it works. Thought I'd mention this in case someone else is experiencing a similar issue

[erico]

I suggest that the next time you disassemble something like the laptop, use your mobile phone and take some photos as the disassembly progresses.

[chris301up]

Yes, Thats fair comment it you own a phone with a camera? I don't. My phone is a very old Nokia. My Son did this for me so that I could post a reply in case someone else has a similar issue? Still don't know why routing the cables differently sorts the problem though. Does it? Thanks for the reply

[erico]

Routing the cables above provides a medium that isolates the hall effect sensor from being activated. 

It is a bit like the Marconi cage effect which isolates a device from signals outside of the cage.