Toshiba Satellite C50-A won't power down

[ju123]

Hi guys,

So, I've been racking my brains on this one.

I have a Satellite C50-A which I'm repairing for a friend.

I recently replaced the main board due to failure.

Following this, absolutely everything works perfectly, except for the fact it won't power down.

Initially, shutting down via Windows would shut the OS down, screen would turn off (noticed the lighter black go to what looks like the darker black powered off screen as though the backlights have powered off), however the laptop was still running internally with a spinning CPU fan, appropriate power led lit etc. It's as though the laptop shuts down but just can't cut off the final bit of power to complete the power down.

Alongside this, no matter what state it is in, holding the power button will get the laptop to the above state where it has almost shutdown.

To boot the laptop back up, the battery and charger has to be removed, then after plugging back in, power button kicks up the laptop and all is ok until you want to shutdown again - please note that the laptop will restart correctly, just not shutdown.

A few troubleshooting steps I have tried with no change in results:-

-Used clean install of Windows 10
-Removed hard drive and tried to power off using button after POST and also booted into Windows RE env using Macrium rescue
-Removed power button board ribbon cable, shorted pins to boot up into Windows and then attempted power off through usual shutdown procedure
-Uodated BIOS from 1.2 to 1.3
-Removed CMOS battery and reset BIOS settings
-Disabled any funky bios features i.e wake on etc and disabled all hardware devices i.e pointing device, NIC etc.

Apart from purchasing another board to test I'm totally out of.options.

Any ideas here would be hugely appreciated!

Thanks for any time taken to read or respond to this question.

TLDR: Laptop won't fully power down, even when holding power button and taking Windows out of the equation.

***Updates on tests following the original post but NOT resulting in success***

-Removed WiFi card
-Removed RAM - got the usual beep upon power up, held power button and same state as original issue, but beep disappears, again as though it's shut down but still can't cut that last bit of power off.

[mon2]

Re: Toshiba Satellite C50-A won't power down

Is there a WIFI module onboard this logic board ? Remove it and try again.

PCIe devices have a WAKE function that if not implemented correctly can cause this fault.

[ju123]

Re: Toshiba Satellite C50-A won't power down

Is there a WIFI module onboard this logic board ? Remove it and try again.

PCIe devices have a WAKE function that if not implemented correctly can cause this fault.

I was meant to try this and forgot, however I just gave this a go and unfortunately no change.

Thanks for the response, it's much appreciated.

[ktmmotocross]

Re: Toshiba Satellite C50-A won't power down

try it on ubuntu? windows 10 have MANY problems on Toshibas

[mcplslg123]

Re: Toshiba Satellite C50-A won't power down

System not shutting down properly can be for many reasons.
01. Does intel hd driver is installed properly. If u install this driver and screen goes blank, problem is very likely in gfx area and it'll result in incomplete shutdown.
02. Pci_wake signal. This should be removed when shut down. But if it is not removed, system will not shutdown completely. Usual culprits are wifi,lan chip,sound card.
03.If enable is not removed from dc-dc converter. Usually replacing the dc -dc converter cures it.
04. Lastly it could be bad pch but chances r very slim.

There can be many other reasons but first check all these listed aspects