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#1 |
New Member
Join Date: Jun 2018
City & State: Toowoomba
My Country: Australia
I'm a: Knowledge Seeker
Posts: 2
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![]() Hi. I am in need of some assistance. I am trying to track down a short in this board and I am having limited success. Fuse F7140 is blown and I have removed U5450, R5450 as well as fuse F7700 and the short disappears past these components but I am unable to locate it. The only thing I can think of is that it has an internal short within the board. Any help would be appreciated. Thanks
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#2 |
Member
Join Date: Sep 2017
City & State: san diego
My Country: United States
I'm a: Knowledge Seeker
Posts: 22
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![]() Insert voltage?
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#3 |
New Member
Join Date: Aug 2016
City & State: Nottingham
My Country: United Kingdom
I'm a: Knowledge Seeker
Posts: 3
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![]() did you find out what was causing it?
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#4 |
New Member
Join Date: Jun 2020
City & State: Buffalo NY
My Country: USA
I'm a: Knowledge Seeker
Posts: 1
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![]() Hey!
I have solved this type of issue once before on this exact board. Pin one side of F7140 was getting the 8.6v but the pin 2 side was shorted to ground. The fuse was blown as well. I didn't have the means to inject voltage so I replaced the fuse. Once I did that the pin 1 side of the fuse became shorted to ground as well. I then plugged in the magsafe and dripped alcohol all over the board to see if anything got super hot. This is when I found C7313 sizzlin'. After replacing it, I got fanspin and the board was fully functional. The short was gone. Hope this helps. There are a lot of capacitors on the G3H line that could be blown and shorting to ground. This is my first post. I wanted to post regarding sourcing the F7140 fuse. I have another Air with a similar issue and don't have any fuses left on donor boards. |
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#5 |
New Member
Join Date: Jul 2020
City & State: Lugansk
My Country: Ukraina
I'm a: Knowledge Seeker
Posts: 1
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#6 |
Boardkiller
Join Date: Feb 2014
City & State: slovakia
My Country: slovakia
Line Voltage: 230VAC 50Hz
I'm a: Hobbyist Tech
Posts: 2,655
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