A1466 Logicboard with hole

Bob_1972

New member
Hi guys , this is a MacBook Air A1466 Logicboard - 820-3437. See attached photo. There was once F7700 where the hole is now. Looking at the Boardview it would need around 19 jumper wires. Would anyone attempt this ? if so do you have any advice?

Thanks - Bob
 

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2informaticos

Administrator
Staff member
19 wires for?
Just need to run a wire from any PPBUS_G3H point to F7700.
Solder new fuse in one point only: or bypass it directly.

Be aware on the opposite side, may need to rebuild some traces.
Not necessary if thunderbolt is not used.
 

Bob_1972

New member
Super, there is no damage on the opposite side. It also seems R5490 is missing, you can see its gone in the photo.
 

Bob_1972

New member
Hi 2informaticos, I have replaced F7700 by soldering pin 2 to its pad and then running a wire to pin 1 of C3080. I have a short on C7712 and C7713. I have a Flir One Pro LT and the attached shows the fuse and Q7706 glowing. Looking around the area C7799 was discoloured so I have replaced it. I have removed Q7706 and still get the short. the amperage is 0.24A and I now get a green light on the charger which I never got prior. I replaced U7701. Any ideas ?
 

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2informaticos

Administrator
Staff member
Where exactly do you note the short?
Power rail name, please.
Did you clean internal edge of the hole?
 

Bob_1972

New member
Hi, I have removed Q7706, F7700 and C7782 and I still see the exact same hotspot. I think the issue is that the short is on the board now, I think. I think this because if I drop alcohol over the area it evaporates very quickly in the hole and I can even see the alcohol sizzling. Is there anything that can be done about this ? obviously I am not at your level or I would not be asking so if you can think of anything else please say as I may not have thought of it.
 

Bob_1972

New member
Hi thanks for coming back to me. I have removed F7700 and re run the wire from the pad where pin 2 of F7700 should go to pin 2 of F7140 and the short has gone. I am getting 225mv on pin 2 of F7140 now. Checking the thermal camera the temprate has gone down and I dont see the same alcohol evaporating of the area with the hold. See image 1. However I have now got a hot spot around Q7130, image2. Can you also advise what to use to polish , I have never done this before.
 

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2informaticos

Administrator
Staff member
Please check in diode mode on power rails and find the short.
If a component heats, should have bad reading on output pin...
 

Bob_1972

New member
Thanks I will do this, can you tell me how you would polish the burn hole? I have never needed to do this before.
 

Bob_1972

New member
Hi, I know for sure that the short is in the hole, I have scraped and tried to "polish" with a black stick. Can anyone offer any tips of removing shorts like this?
 

Bob_1972

New member
I have managed to , I think, remove the short. Like I said I have soldered a wire to pad 2 of F7700 and run the wire to pin 1 of F7140. F7140 is reaching 140 degrees now so I still have an issue but its moved. Any ideas or pointers would be great, is running the wire between these points correct? looking at the board view it seemed to be.
 

2informaticos

Administrator
Staff member
That is less than 5 ohm, still short; 2-3 ohm in fact.
I hope you've removed power, before measuring in diode mode.
 

Bob_1972

New member
Hi , so yes I did remove the power. I know you are mega busy but is there anything that you can add that might help me here ?
 

2informaticos

Administrator
Staff member
No other way than eliminate the short.
If you are sure the short is inside board (between copper layers), is not easy at all.
 
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