This 12 Pro came in for no power.
USB Charging was like 0.44A
When you boot from DCPS, the current draw would jump up only a little, like 30mA at most, then back to zero & repeat. Sometimes, it would just stay at 0 to 2mA
I split the sandwich & it booted!
I put it in the sandwich jig & no power. Back to same symptoms
So went back to top board only & it went back to the same original symptoms.
I was trying to rule out the bottom board issue, but it had the same symptoms as when it came in.
Putting pressure on the whole top board then trying to boot again, it booted! So the issue is very sporadic. But I also was fearing the issue was the CPU.
Tested another bottom board & back to dead. Tested top board only & it booted. Wiggled the top board only & it stopped booting.
This made me think... something must be loose. I removed the shield around PMIC, as there are lots of coils around it & started poking them all. Almost none are underfilled on this model. All were good
I then see there's a coil near the CPU, L4200, on LX_SYS_BOOST and sure enough, it popped right off. Just a very light poke, it broke off.
Tested again & it was doing the same symptoms as the beginning.
Replaced it from a donor & it booted. And even after wiggling and twisting the board lighty, still boots! So it's solved.
Reballed the sandwich & invoiced the customer.
I made a quick little video about it, which you can see here: https://www.tiktok.com/@vcc_board_repairs/video/7142677806932036907
🙌
If you have a Seek Thermal Cam, you're missing out if you don't have a VCC Seek Stand: https://www.vccboardrepairs.com/buy-seek-stand
Injured Gadgets just got these back in stock, so get them while you can!
It can take us a while to build these out sometimes, so they're sometimes out of stock for a while, but we're working towards always having inventory ready to build more as they sell out.
This stand makes using a thermal cam so easy. So much better than any other thermal solution on the market.
It allows you to get real close up (using my Macro Lens), and easily find where the short is coming from.
Plus it's hard free, so you can have your hands free to try to boot the device from DCPS, while having an image that is in focus & not moving around.
You can even record a video through the app, while you inject voltage into the short, so you can go back & see exactly which component was it that was heating up.
Save yourself lots of time by getting a Seek Cam, Stand & Macro Lens! ...
Anyone who is doing game console repairs, knows how many screws you need to remove to access the motherboard.
Especially the PS5, with the 5,000 screws or so.
If you don't already have an electric screwdriver, GET ONE ASAP.
🌟 Cordless Screwdriver with T9 Bit: https://amzn.to/3E5duCj
🌟Extended T9 Bit: https://amzn.to/3c4YJac
It's rechargeable through micro USB and allows you to easily swap the tips out. You can also fold it to be straight or L shape.
Let me know below if you are already using an electric screwdriver 👇👇
Have I got a please bro . Hahah
Thoughts on what is missing. Well it looks like a coil, but value guesses? It's an Omnex R160 wireless controller
This Pixel 6 came in for no power after another repair shop tried to repair the Display FPC connector (See pic1)
By the looks of it, they struggled badly trying to get this soldered on lol
So I found there were signs of overheating on the CPU and EERPOM chip, which was likely the fault. (See pic2)
I went through the full CPU Swap process, transplanting the CPU, RAM, UFS and EEPROM, only for the phone to bootloop & then give me the error in pic3
Unfortunately, it seems like something corrupted the UFS in the process, causing data not to be recoverable
This makes me sad, as an FPC replacement should be one of the easiest solder jobs to do, but this is what happens when inexperienced techs practice on customer's devices ðŸ˜
I totally get the urge to try it. You see videos... it looks easy.. you got some random hot air station & cheap iron combo from amazon
So why not?
Well this is why not.. you can totally kill the customer's device & data
If you want to learn how to solder, practice on ...
Had an S23 Ultra come in for a simple display connector issue… but it turned into a mess after someone tried to fix it themselves.
Glue all over the connector, uneven solder, no flux used, pads almost compromised… the whole thing was shifted and barely hanging on.
This is one of those repairs that looks easy on YouTube, but in reality takes a lot of control, the right temps, and proper prep.
Ended up doing a full FPC replacement and got it fully working again.
Curious how you guys approach these:
Do you pre-tin connectors or go straight install?
Hot air only or hybrid with iron touch-up?
What temps / airflow are you running for these Samsung FPCs?
Also… how often are you seeing DIY attempts make things worse lately?
Full video here:
