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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Re: MacBook Air 820-00165 PPBUS-G3H Short to ground
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Re: MacBook Air 820-00165 PPBUS-G3H Short to ground
did you find out what was causing it?Comment
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Re: MacBook Air 820-00165 PPBUS-G3H Short to ground
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.Comment
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hello everyone , working zebronics power suply 450 watts , 5v ,3.3v givin short to ground black wire, also in circuit at output, resistor was charred but shows right values , after removing resistors 39ohms, 51 ohms, there was no short , no continuity beeps with ground , but after replacing new resistors (now i am not switching it on) ,again short still exists . when i put bigger ohm resistor like 100k ohm , no short beeping sound comes , lower ohm resistor gives continuity beeps ,other big ones donest , as its a working psu , i am confused what to remove now or how to go further now .
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Greetings to the entire forum, I ask you for help because I'm going crazy. A dear friend of mine gave me a macbook pro M1 A2338 that only works with an external screen. With the internal one, no backlight or image. Only the external display is detected from the system settings.
First I changed the display flat, then I made a backup with time machine and tried a reset in dfu but nothing to do, always the same problem.
I analyzed the logic board, it shows no sign of liquid or visible damage. I then moved on to examine the logic with the thermal camera and found that the UP701 chip was... -
Greetings to the entire forum, I ask you for help because I'm going crazy. A dear friend of mine gave me a macbook pro M1 A2338 that only works with an external screen. With the internal one, no backlight or image. Only the external display is detected from the system settings.
First I changed the display flat, then I made a backup with time machine and tried a reset in dfu but nothing to do, always the same problem.
I analyzed the logic board, it shows no sign of liquid or visible damage. I then moved on to examine the logic with the thermal camera and found that the UP701 chip was... -
Hello, I have a pcb from an e scooter which had a faulty diode but even after removing it from circuit, it still has a short to ground on the three components circled. I have removed every cap on the board and tested one by one and the short is still there and all the caps test ok. Could this be because I haven’t put a diode back on it yet or where do I go next please? -
this machine came to me as DOA and immediately found the issue as a 12v short to ground. Is it okay to inject voltage into that rail or does it have a potential path to the cpu or something?
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