Question Wii U10 help

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Its been a long time coming but I'm finally starting a wii portable build.
Forgive me if there is already a thread for this, I'm relatively new to the site and couldn't find what I was looking for. I did find some troubleshooting and I did follow the suggestions (more on that later)

I have a 4 layer board and just performed the U10 swap. I used 38 gauge magnet wire between the U10 and GPU via. Instead of cutting the trace on the board, I placed a small piece of electrical tape below the pin. I have not performed the trim yet; so as of now, I have a full board.

After a few attempts at getting a good solder joint on the GPU via I was able to power on the Wii successfully. Unfortunately at some point my solder joint to the GPU via broke and the wire came loose. I re-soldered the wire but since then I cannot get the wii to turn on.

So here are the symptoms:
The status led on the front turns red when I first plug it in
When I press the power button, the led flashes green then turns off.

Here is the troubleshooting so far:
I checked continuity on the U10.
I have a blob of solder connecting the 3 pins to ground. continuity between those pins and ground is good
Continuity between the 3.3V pin and another 3.3V source is good.
Continuity between the U10 and GPU via is good (I checked this by measuring between the U10 and TP119)
I also checked the vias around

I also used a oscilloscope on the U10 to GPU via to see if any power was passing through the U10. I am getting what looks like ~2.5 V to the GPU for about 4ms before it turns off, see picture. My o-scope only has one channel so I can't really measure what the delay between power on and 3.3V to the GPU.

Per some suggestions from other threads, I also checked resistance between power and ground and from power form to power form
3.3V to gnd =~3.6k
1V to gnd = open
1.15V to gnd = ~42 ohm
5V to gnd = ~50k
no shorts between power forms

Does the behavior indicate that the U10 chip is bad? I'm not sure what else it would be at this point. Like I said before, I did get a good boot at one point, but I did re-flow solder on the U10 and maybe I heated it up too much...
I still have the U9 as a backup but I'm hesitant to remove it and replace the U10 if the U10 isn't actually bad.

Any help would be appreciated. Thanks in advance!
 

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cheese

the tallest memer in town
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I'd say check for shorts, when the light goes from green to off that usually means something is shorted. You may also want to reflow those joints with some flux, and clean all the spots you were soldering with some IPA
 
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Didn't find any shorts... but I ended up removing the U9 and soldering it in place of the U10. I also replaced the 38 gauge magnet wire with some 28 gauge stranded and routed it through one of the mounting holes instead of through the via. That seemed to do the trick.
 
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