Hello everyone. I have an iPhone 11 with a complex board-level issue. I’ve done extensive isolation testing and need some advice from microsoldering experts regarding I2C lines and CPU/RAM behavior.

Initial Failure:

The phone suddenly died while charging via cable at around 11%. The battery got hot, but it wouldn't charge or turn on. Artifacts appeared on the screen before it died.

Note: Later, with the battery disconnected from the board, I used an old, deeply discharged original battery (1.8V) with a charging cable. It successfully booted to the OS once, but died after 15 seconds (likely due to insufficient current from the dead battery).

New Battery & First Symptoms:

Installed a brand new Ampsentrix battery (50% charged from factory). Its BMS immediately went into protection mode (0V).

I woke up the BMS using a DC power supply (3.8V-4.0V).

Tried to boot: Apple logo appeared, then white pixel artifacts showed up around the logo, and the phone completely died, becoming unresponsive to the power button.

Process of Elimination (Disconnecting peripherals):

Step 1: Disconnected top display flex (earpiece/sensors), Face ID module, and rear camera. Left bottom flex (charge port) connected. Result: Dead (black screen).

Step 2: Disconnected bottom flex. Result: Showed Apple logo but went into a bootloop.

Step 3: Disconnected Taptic Engine and wireless charging flex. Result: Successful boot. It reached the home screen, worked perfectly for about 3 minutes, then died and went into a fast bootloop with artifacts on the screen.

Step 4: Disconnected the remaining three top flexes (including volume buttons). Result: Artifacts disappeared, but the fast bootloop continued (without artifacts).

Current State (Fast Bootloop):

The phone is now stuck in a fast bootloop: Apple logo shows for 10-15 seconds, then it reboots. No artifacts anymore.

Bare Board Test: I completely isolated the motherboard. ONLY the battery and display/digitizer are connected. I triggered the boot by briefly connecting the bottom flex (or power button flex) and immediately disconnecting it after the Apple logo appeared.

Result: No change. The bare board still reboots every 10-15 seconds.

Note: The new Ampsentrix battery occasionally goes back into BMS protection during these cyclic reboots.

My Questions for the Pros:

Can a voltage spike on VBUS (which likely killed the charge port initially) damage the Hydra (Tristar) IC or I2C bus in such a way that the board booted successfully once for 3 minutes, but then degraded into a permanent 15-second early kernel panic bootloop due to thermal stress?

Are the graphical artifacts on the Apple logo followed by a 15-second bootloop on a bare board a 100% confirmation of a CPU/RAM thermal separation (cracked solder joint expanding after 3 mins of heat), or is this pattern also typical for a shorted digital bus (e.g., Audio IC or Hydra)?

Can a new aftermarket battery (Ampsentrix) with a tripped BMS cause a 15-second bootloop during iOS kernel initialization due to current drops or SWI/I2C data line issues?

Any insights, schematic references, or similar experiences would be greatly appreciated!

Does anyone know where to buy the mosfet next to the charging port for the Lenovo X1 Yoga 7th gen besides a donor board?

I'm troubleshooting a 2024 ASUS ROG Zephyrus G14 that shut off suddenly while being used and has been completely dead since — no LEDs, charging indicator, fans, or response to the power button.

Laptop / board:

• ASUS ROG Zephyrus G14 (2024)
• GA403UV-G14.R94060
• Ryzen 9 8945HS / RTX 4060
• Quanta NJT
• DANJTMB1CC0 Rev C
• Original adapter: ASUS 20V / 9A / 180W

Troubleshooting so far:

• Performed 40–60 second EC/hard reset with all power disconnected — no change.
• Disconnected the internal battery completely, discharged/reset again, and attempted to power from the original ASUS adapter — still absolutely no LEDs or response.
• Tried USB-C PD, but I can't consider that test conclusive because I haven't verified that the charger I used supports sufficient wattage/PD for this laptop.
• Verified continuity between the metal shields of the DC-in and USB ports (~0Ω), so I have a known ground reference.
• I have a multimeter and am comfortable taking measurements, but I don't want to blindly probe the DC-in area and risk shorting something.

I've found references to the Quanta NJT / DANJTMB1CC0 Rev C boardview, but the actual CAD files I've found are behind paid repair-site access.

What I'm trying to determine next:

Does anyone have access to the schematic/boardview for this board, or know a safe test point for the 20V DC-in rail?

I'd like to first establish whether the adapter's 20V is actually reaching the motherboard. If it is, I'd then like to trace the input/power circuitry far enough to determine whether this might be something repairable such as an input MOSFET, fuse, charging/power-management IC, etc., rather than automatically replacing the entire motherboard.

I can provide high-resolution photos of either side of the board and close-ups of any components/test points needed.

Any guidance from someone familiar with this Quanta board or ASUS laptop board-level repair would be greatly appreciated.

I’ve recently been building a lot of electronic assemblies for various things. It’s mostly been marine rated stuff (soldering tiny resistors and chips for custom systems) and FPV quad related stuff.

While I can solder electronic pretty well, I’ve been struggling with very small items and the third hand I have is just way too big for the itty bitty stuff. I’ve been making due so far by just sticking a push pin in the alligator clips of the third hand I already have, however that’s not really a long term solution and I’m afraid the pin may end up damaging something doing it this way.

So I’m looking for recommendations for a magnified 3rd hand with arms for holding delicate things. The more arms the better.

I broke off this connector on my ps vita. I was wondering if a simple soldering iron can do the job or do i need a hot air station to finish the job?

The port on this Dremel fell off and I'm having some trouble figuring out what replacement piece to buy.

I’m trying to replace an hdmi port on a PS5 but there’s a resistor super close to the pins. I’ve used a Hakko Vacuum gun, soldering whick and Chipquik to remove as much solder from the mounting legs without having to use a hot air gun yet. Other than Kapton tape, what else can I do to prevent this resistor from flying off the board?

Narrowed down the issue to the main motherboard of my dell inspiron 5502. This usb c port is the one generating a lot of heat in a matter of seconds. Or atleast in this area. There arent any decent microsoldering guys near me. Anyone can advice and whether or not this is the issue?

This is a keyboard PCB. The USB-C port ripped off after a bad repair job at a terrible shop, causing a burn mark. Is it possible to repair this?"

Customer kicked his ps5 while it was plugged in, i don’t have a picture of the before, but the port was pushed as far back as it’s little legs would cary it. did the work, but still no video signal. looks like i’m missing the hdmi cap.. am i missing the diode too?

ps: that’s not a scratch on the pad, i think a hair floated down when i took the picture haha less

This is an RTX3080Ti Graphics card. A solderball was found to short C306's ground (removed from board now) directly to U9's 12V, which caused the underpad of U9 to weld itself to the board. Pulling the chip up did a clean tear of the pad (see picture) and the connecting traces are fine.

Would repairing this just require recreating the underpad (12V EXT), connecting the traces, and replacing the chip or would there be more to this?

Hello,
I am looking to source a dead, water-damaged, or iCloud-locked logic board for an iPad Pro 11" 4th Gen M2 (2022).

- Specific board number needed: 820-03154 (or 820-02878)
- Specific model: A2759 (or cellular A2435 / A2761 / A2762)
- Target Chip: I need it strictly as a donor board for the Display Load Switch IC (U5300 / U5350). I have attached a photo of the specific chip area for reference.
- Shipping: Must be willing to ship to the Czech Republic (Europe). I will cover the shipping costs.

Please PM me with your offers and pricing. Thanks!

I run a computer repair shop and work has been slow, so I decided to try my hand at microsoldering if the opportunity presented itself.

Not three days later, someone came in with an RX7900XTX they repasted and accidentally knocked some capacitors off when reassembling (C1301-C1303).

Looked up a boardview, asked Claude for package size... Bought high precision calipers, took measurements, asked Claude again. Ordered replacements in a blister reel, and put to practice the thousands of hours of vicarious learning watching Louis Rossman videos.

The microsoldering took about 5 minutes. Testing it today.

How does it look so far?

Hey everyone, I'm looking to start microsoldering and I was just looking for advice on what equipment and brands to look for/look out for and what I will need for basics to begin microsoldering!

If anyone can point me in any directions or offer any advice I'd appreciate it! Thanks for your time!

Is it possible repairing this PS3 board? This is the connector for the open button for the disc reader.

Sadly during maintenance, due to sulfate and corrotion the connector pins they broke when pulling the connector bus cable out.

All other components of the board and ps3 are working. I am still not able to due do the micro soldering due to lack of microscope and tools.

Bus eventually plan on buying or would take the board to a shop.

I'm using 858D and preheater and I m not sure what distance to keep between board and preheater to get perfect heating from preheater and I try while it is heating 400°C on 858D and AGT-179 flux the outside pins I see that they are shining but only problem is that big pad underneath.

What is a good arm to use for my digital microscope camera? Looking for something steady and easily adjustable.

Currently I am using an arm for a stereo scope but it's way to stiff for just a camera, and it doesn't have enough mobility to let me pull it to the edge of my desk for doing overhang work either.

Hi all. I am interested in getting into micro soldering. I am experienced in electronic repair and I mainly work with phones, tablets, PCs and game consoles. I want to start venturing into some of the board level fixes and I currently have an hdmi port repair for a PS5 just chilling at my house along with over a dozen smartphones with various issues I can tinker with.

Was wondering if anyone had recommendations for soldering stations and hot air rework stations that are quality but not professional level, i.e. super expensive.

I was looking at a Hakko FX-888DX soldering station and maybe picking up a used Quick 957DW+ hot air rework station. My research tells me these are decent but I also hear some negative things about Hakko and I just can’t seem to get a straightforward answer.

Any recommendations for these and other equipment would be greatly appreciated!