Acer AOD 270 Shorted with Pictures please help

[tomrush]

i have acer netbook shorted board. i tried to follow the schematic until i came to a resistor i remove and its not anymore shorted. i remove the next mosfets after the resistor thinking its shorted but still problem persists. is there a possibility that the PU2 chip is the one shorted? please help me i have attach image and the schema for reference.
i'm still new to board repair thank you

i put red circle around the removed resistor

[tomrush]

Re: Acer AOD 270 Shorted with Pictures please help

everytime i put back this resistor PR133 no power come in. i remove all component after this the resistor the PQ40 but still shorted. is it possible that this resistor? how to test if shorted and what is the resistance? what i only know is resistor is bad if open or no resistance. thank you please help me i'm still a beginner

[khaahk]

Re: Acer AOD 270 Shorted with Pictures please help

Measure resistance after PR133 (if you have it removed) relative to GND. If it is small (some ohms), then you have short in VIN, this could be all over the board. Then use lab power supply to find the short (of course if you have one).

[tomrush]

Re: Acer AOD 270 Shorted with Pictures please help

yes there is small ohms i measured. as you said sir there is a short in VIN. thank you so much...

i want to know where will i start checking the short. are there common part of board that get easily shorted. what does a lab power supply look like? do i need to have this sir?
thank you for answering my first question

[Ramee]

Re: Acer AOD 270 Shorted with Pictures please help

This is what you need, adjustable power supply. You can get from here.

http://www.aliexpress.com/item/Free-...668592085.html

[tomrush]

Re: Acer AOD 270 Shorted with Pictures please help

i have ordered this adjustable power supply from our local store. hope to have it in a week.

sir ramee & sir khaahk i will order this power supply to trace shorted component, right? but while i'm waiting can i trace the shorted component. can this smart tweezer help me to trace the shorted component? if i can, what common component get shorted. i appreciate your help.

[khaahk]

Re: Acer AOD 270 Shorted with Pictures please help

Capacitor is the most likely component to fail. As they are all parallel, tweezers will show short everywhere. You will have to remove them one at a time to measure. Visual inspection under microscope sometimes helps.

[Ramee]

Re: Acer AOD 270 Shorted with Pictures please help

@tomrush>> we are in boat, still learning how to test components.

First, learn how to feel the heat by touching components while charger is pluggd in.

Second, if you find something gettin hot, like cap, check for resistance or remove it

from board to test it.


About testing mosfet, go to youtube.

[tomrush]

Re: Acer AOD 270 Shorted with Pictures please help

thanks for the response sir. i'm gone for few days and finally got this avr of mine. i'm trying to practice to touch components to see if there is a heat. i found one mosfet overheating. i replaced it and the power is on yet no display. i'm in progress now trying to follow visual instructions from youtube. but while doing this does this little ceramic capacitors really get easily shorted because it's really pain in the ass to remove them one by one. but i appreciate if this is really the only solution.