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Jurisprudence

macrumors member
Original poster
Dec 24, 2007
51
0
Hi all, hope someone can help with this. I picked up an MBA Rev A 2nd hand which was sold as broken. It didnt power up and no light comes on the AC adapter. I've just replaced the logic board with one I got from an ebay seller who assured me is working (good rep and his story of breaking for parts due to hinge damage seems plausible as he also gave me the top casing which shows damage to hinge cowel). Again with the new logic same again, it looks like this

-No power led on AC adapter, it does power my MBP and when using the MBP AC on the MBA there is no light on the adapter again
-No boot sounds
-No display
-No clicking sounds (although there is an almost imperceptible ticking approx every 1 second when plugged in, doesnt sound like a HDD ticking though and you have to press you ear right to the casing to hear it)

I'm looking to replace the power connector for the MBA as I can't think of any other components which would prevent powering up. I have tried to boot with the battery in and removed, no change.

Anyone have any idea if there could be any cause apart from the power connector on the MBA which could cause this to happen. Going nuts pumping money into what appears to be a dead duck. Cheers.
 

Synchromesh

macrumors 6502a
Jul 15, 2009
619
120
SF
Try resetting the power manager (see procedure on Apple website), swap power board, check power supply. If nothing works, most likely board is crap.

One last fix is to let it sit for a couple of days with no power connected and disconnect the battery. Sometimes helps.
 

mgartner0622

macrumors 65816
Jun 6, 2010
1,018
0
Colorado, USA
If what the post above me said doesn't work, I would definitely think the board you have is bad. There should be no reason that it would not power on.
 

Jurisprudence

macrumors member
Original poster
Dec 24, 2007
51
0
Thanks for the replies guys, very much appreciated. I've tried reseting PRAM and SMC no effect. AC adapters are definitely good. Part of my dilemma, apart from this turning into a very uneconomical escapade is I have to assume that the 2nd logic board is good and its another component at issue.

So I'm trying to deduce if any of the other components would prevent an initial boot sequence even beginning. I cant see anything but the DC-in power board causing this. With my other macs a HDD, audio board, airport etc would cause errors on boot but would allow it to begin booting.

Apart from my assumption as to the logic board is my theory correct in people opinions that it can really only be the DC-in board. Cheers.
 

ZipZap

macrumors 603
Dec 14, 2007
6,112
1,467
Get the seller to take it back or file a claim via paypal buyer protection.

Perhaps you can take it to a repair place for a diagnosis then decide not to repair there because of the cost. I am sure they will still charge something but it could be fairly low.

Otherwise, you buy this component and then suspect that component and it gets expensive.
 

Jurisprudence

macrumors member
Original poster
Dec 24, 2007
51
0
Thanks for the reply ZipZap. I hear what your saying about both returning to the ebay seller the spirally cost of paranoid component purchasing for this kind of thing. But assuming the logic board is good I can see only one other component this can be causing this type of failure, the DC-in board. I've found one for approx €11 compared to the €425 I've now wrongly spent on this project. What do you think?
 

ZipZap

macrumors 603
Dec 14, 2007
6,112
1,467
Thanks for the reply ZipZap. I hear what your saying about both returning to the ebay seller the spirally cost of paranoid component purchasing for this kind of thing. But assuming the logic board is good I can see only one other component this can be causing this type of failure, the DC-in board. I've found one for approx €11 compared to the €425 I've now wrongly spent on this project. What do you think?

You've come this far...€11 seems small for final confirmation.
 
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