When your iPhone X won’t charge, it can be a frustrating experience, especially after multiple unsuccessful repair attempts. In this guide, we’ll walk you through a detailed troubleshooting and repair process to resolve charging issues, focusing on cases where the phone has already been worked on by other technicians.

Phone Details:
Model: iPhone X
Announced: 2017, September 12
Defect Phenomenon
The iPhone X was brought in with a non-functional charging port, and despite being repaired by several shops, the problem persisted. There was no charging symbol when connected to a charger, and tests using a USB multimeter charger detector showed no charging current.
Troubleshooting the Charging Issue
1: Initial Inspection

After disassembling the phone and inspecting the motherboard, it was clear that the board was dirty and oily, with excess flux paste visible. This was an immediate red flag, as improper handling and poor-quality repairs can lead to further complications.

2: Diode Value Check
The next step was to measure the diode values on the battery connector. Fortunately, all the diode values were within the expected range, indicating that the issue wasn’t with the basic battery circuitry.

3: Motherboard Separation


Given the state of the motherboard, we decided to separate the two layers for a closer inspection. Placing the board on a heating platform allowed us to separate the layers, revealing a messy interior full of low-quality solder paste flux. Additionally, the charging circuit components had been poorly resoldered by previous technicians.


Repair Process
1: Cleaning the Motherboard
The first and crucial step was to thoroughly clean the motherboard using a PCB cleaner. This not only removed the excess flux and dirt but also allowed for a more accurate assessment of the board’s condition.

2: Replacing the USB IC
Based on our repair experience, the USB IC often has a high failure rate and is a common culprit in charging issues. Here’s how we replaced it:
- Remove the Original USB IC: Carefully desolder the existing USB IC using a hot air gun.
- Prepare the PCB: Apply solder paste flux to the area and clean the PCB with solder wick and a soldering iron to remove any residual tin.
- Install the New USB IC: Align the new USB IC in the correct position and use a hot air gun to solder it securely onto the motherboard.

3: Testing the Repair
After allowing the motherboard to cool down, we temporarily assembled the phone and connected it to a DC power supply. The good news? The phone charged normally, indicating that the repair was successful.

4: Recombining the Motherboard
The next step was to recombine the two layers of the motherboard using the heating platform. Once reassembled, we tested the phone again, and all functions, including charging, were working perfectly.

Tips for Technicians
- Keep It Clean: Maintaining a clean motherboard is not just a best practice but a sign of respect for your customers. Always clean off excess glue, solder paste flux, and other residues after repairs.
- Attention to Detail: Reapply any stickers and foam that were removed during the repair process. If possible, solder back the shielding covers to protect the components.
- Quality Matters: Using high-quality materials and tools is essential to ensure the longevity and reliability of your repairs.
Conclusion
The iPhone X charging issue was resolved by identifying and replacing a faulty USB IC, along with thoroughly cleaning and reassembling the motherboard. This guide highlights the importance of proper repair techniques and attention to detail, ensuring that the phone is returned to the customer in optimal condition.
If you’re facing a similar issue or have any questions about iPhone repairs, feel free to reach out or leave a comment below!