Since Apple introduced USB-C with the iPhone 15 series, many users have encountered unexpected charging issues—particularly when using non-certified cables. In this guide, we’ll walk you through a real repair case of an iPhone 16 Pro that wouldn’t charge. You’ll learn how we diagnosed the problem, the tools we used, and how we successfully resolved the issue by replacing the USB IC and controller IC. Whether you’re a repair technician or a DIY enthusiast, this tutorial is packed with valuable insights to help you address USB-C charging failures.
Step 1: Diagnose the Issue
The iPhone 16 Pro would not charge at all. First, we powered off the device and removed the back glass.
Step 2: Replace the Charging Port
We started by addressing the most common suspect: the charging port. Replacing it with a brand-new unit allowed us to rule out any port-related issues. However, the phone still wouldn’t charge, indicating a more complex problem.
Step 3: Inspect the Motherboard with REFOX Bitmap
Next, we removed the motherboard and used the latest version of REFOX Bitmap, which now supports the iPhone 16 series. Bitmap’s Perspective Overlay Mode enables precise alignment over the microscope feed, helping us clearly view circuit routing and test points. Using this, we identified the USB IC lines on the connector and checked the resistance with a multimeter.
- Expected resistance: ~570
- Measured resistance: 36 → indicating a short circuit in the USB IC.
Step 4: Remove and Inspect the USB IC
The USB IC (integrated circuit) is located under a metal shield. Here’s how we removed it:
- Applied low-temp solder paste
- Blended it with high-temp solder using a soldering iron
- Added high-temp tape for protection
- Removed the shield
- Applied flux and carefully lift the USB IC with a blade
After removal, we tested again:
- Reading: 1 → Normal
If it still reads 36, further troubleshooting would be required.
Step 5: Identify the Root Cause
Under the microscope, we found that the pin layout of the non-Apple USB-C cable was incompatible, likely causing electrical damage to the USB IC. Important reminder: always use MFi-certified (Made for iPhone) accessories.
Caution: Using a non-Apple Type-C charging cable may damage the USB IC.
Step 6: Replace the USB IC and Controller IC
When replacing the USB IC, we also replaced the USB Controller IC to ensure full compatibility and function.
USB IC Replacement Steps:
- Add solder flux to the pad
- Use a medium-temp soldering iron to neutralize old solder
- Clean the pad with a solder-wick
- Add flux again and align the new USB IC
- Heat and solder it into place
Now we have tested and the reading is back to 570
USB Controller IC Replacement:
- Heat the desoldering platform to 190°C
- Use a hot air gun for motherboard separation
- Remove and replace the USB Controller IC using the same soldering process
- Clean pads and reball the motherboard before reassembly
- Recombine at 190°C
Note: If you are swapping the USB IC, make sure to replace this one as well or the new IC work properly.
Step 7: Final Assembly and Testing
We reassembled the motherboard, placed it back into the phone, powered it on, and tested the charging function — it worked perfectly!
Tools & Parts Used
- REFOX Bitmap (iPhone 16 Supported)
- Multimeter
- USB-C Charging Port (replacement)
- USB IC
- USB Controller IC
- Low-temp solder paste
- Medium-temp solder
- High-temp tape
- Soldering iron
- Solder flux
- Solder wick
- Microscope
- Blade
- Hot air gun
- Reballing platform
Conclusion
This iPhone 16 Pro charging issue was caused by a shorted USB IC due to a non-certified USB-C cable. With precise diagnosis using REFOX Bitmap and careful replacement of the USB and controller ICs, we successfully brought the device back to life. If you’re a technician, using the right tools and understanding IC-level repairs is crucial. Always educate your clients about using certified accessories to avoid similar issues.
Got questions? Drop a comment below — we’d love to hear from you!
