Aspire one 521 Short - Common problem?

[Adept PC Repair]

I have an Acer Aspire one 521 with a short-circuit fault which seems to be a common problem.

The motherboard obtains power from the jack and charges the battery, apon holding down the power button however, the charge light goes out and nothing happens.

I've stripped the unit down to the motherboard and can hear a slight spark (clicking) sound near the LED's to the front.

I've read on the internet loads of people with exactly the same problem, but no solution.

Anybody here come across this? As it seems a common problem I thought someone may have. Otherwise i'm just going to have to quote for a board.

[NYJimbo]

We had one last year and after tearing it down to just the board it worked, putting it back together we figured it was the video cable. Many times a circuit or component that is not powered until you hit the power button is what will "wake up" the short and kill the machine. So it could be this or something else. But always work your way up from a isolated board when looking for a bad component in these situations. I dont know if you are testing it with ANYTHING connected to the board or just the pure board itself.

This is a video of a ZG5, watch what he does, with the power button on the right and then after he disconnects the video cable.

I suggest turning off the audio when you watch it, I dont know why people have to put irritating music to these things. Either they should talk or leave it silent.

Good luck.

http://www.youtube.com/watch?v=gkP5KiCS9fE

[Adept PC Repair]

I looked at that before posting here but thanks for hyhr suggestion.

I have nothing at all connected and the problem still occurs. I've even removed the heatsink, reflowed the cpu and chipset, removed wifi card. Literally nothing but board and the same symptom is there. The board looks pristene, and is very hard for me to test as it needs me to measure voltage while the power button is pressed.

I just hoped it was a common problem and someone got to the bottom of it, it is definitely an smd by the looks of it.

[NYJimbo]

Originally Posted by Adept PC Repair

... it is definitely an smd by the looks of it.

Yeah, if you're down to the bare board and it looks clean then you would have to go through each component. What I don't like about these kinds of failures is it can be many different faults but they produce the same (or similiar result) and everyone out there in the forums thinks its the same exact thing. It could be a faulty coil with one person or a power mosfet with another or even one of the large control chips, but its impossible to trace and who can figure out what a large TSOP or PLCC is doing when you hit the power.

Does it do it with either AC OR battery alone, not together ? We had a Alienware M15x in here that would do that with the AC unit plugged in but not with the battery. Ended up being something in the power distribution onboard but couldnt isolate it either.

Sounds like its either a loss or get a cheap mobo on ebay.

[Adept PC Repair]

Yes, it does it with battery alone, charger alone or both together.

Customer has agreed to a new board so i've got one ordered.