Maker Pro
Maker Pro

Need a little help repairing a Toshiba Laptop

Daniel Hodapp

Dec 31, 2015
2
Joined
Dec 31, 2015
Messages
2
Hello everyone,
My brother recently tried to upgrade the ram on his laptop and somehow screwed up the motherboard power supply. The laptop worked fine off of battery power... until it ran out of power, but will not boot from the DC supply or charge the battery. The DC supply outputs a healthy 19.34 V and I believe it works fine. When probing the USB port while plugged in I get a strange result. Instead of a constant 5V, I get a constant 3.8V-4V that pulse up to 5V every second. If I plug in a USB led strip, it drops to 2.2V and still has a pulse every second to about 4.8V. I'll attach some photos of the data with and without the usb led strip.

Without the led strip:
WithOutLEDStrip.jpg
WithOutLEDStrip_CloseupofPulse.jpg
This is with the led Strip:
WithLEDStrip.jpgWithLEDStrip_CloseupofPulse.jpg

Thanks Everyone!
 

Daniel Hodapp

Dec 31, 2015
2
Joined
Dec 31, 2015
Messages
2
On further inspection the main power trace looked like the images below, with the cut off every second. It looks like something is overloading and cutting off.
MainPowerRail.jpg MainPowerSupply_2.jpg
 

elebish

Aug 16, 2013
177
Joined
Aug 16, 2013
Messages
177
Substitute the power supply to eliminate that as the problem.
 
Top