Replacing a faulty hard drive printed circuit board is not an easy task. The new PCB must be matched to your hard drive. Without following the necessary steps to change your new circuit board, your hard drive will not function properly and the data will not be accessible.
What is a PCB?
Printed circuit boards (PCBs) on hard drives supply power between the various components that make a hard drive work. If you have ever handled a hard drive, you can recognize the PCB as the green or blue board on the bottom of the device.
In extremely simplified terms, the board “tells” the hard drive how to operate. It processes signals from the computer and allows the drive to transmit information to the central processing unit (CPU). However, it is not the primary storage space for user data and it contains no mechanical components.
Common issues affecting the PCB
A printed circuit board is fairly resistant, but it can be damaged during normal operation. Some common causes of printed circuit board failure are listed below, along with tips for preventing premature damage.
- Extreme heat: the inside of a computer can get extremely hot, especially if the user does not take the necessary precautions to provide adequate ventilation. Heat can eventually cause electronic malfunctions.
- Damage from improper handling: electrostatic discharges can permanently damage electronic components. Always ground yourself before handling your hard drive.
- Damage caused by a faulty power supply: a computer power supply can send inconsistent levels of electricity through the motherboard and to components, resulting in damage. High-quality power supplies are well worth the investment.
- Damage caused by power surges: it is recommended to keep every computer on an uninterruptible power supply (UPS) to prevent surges from damaging printed circuit boards. Power surges can also affect other computer components, which is why a UPS is an essential means of protection.
- Manufacturing issues: although rare, some printed circuit boards have manufacturing defects that cause components to come loose. This can happen even when the hard drive operates in a reasonably well-controlled environment.
Guide to replacing the PCB
Before replacing the printed circuit board, make sure it is a compatible match and that its firmware is transferred. Read this guide carefully before replacing the PCB.
Examine the printed circuit board to see if a ROM chip is present. The ROM is usually an 8-pin chip (4 pins on each of 2 sides) marked U12 on Western Digital drives, or U6 or U5 on Hitachi drives. There is generally only one 8-pin chip on a printed circuit board. You will likely find a number starting with 25 on the chip. Western Digital USB-powered printed circuit boards and some newer, higher-capacity Hitachi hard drives have 2 ROM chips, so feel free to replace both.
For Western Digital PCBs, find a white U12 marking on the chip side of the printed circuit board. A missing chip in place of U12 would indicate that the printed circuit board’s firmware is built into the controller chip. This chip can be transferred by a professional.
Once the chip has been located, replace the PCB chip. If you do not feel comfortable replacing it yourself, contact a local professional. Do not entrust this task to an unqualified party, as this chip is vital for data access. An overheated ROM chip can lead to significant damage and data loss.
If you have soldering experience and the necessary tools, you may attempt to replace it at your own risk. The tools needed are: a hot air station or heat gun, metal tweezers, a gripping tool, and optional soldering flux. Start by attaching the new board to a table with the chip ready. You can apply tiny amounts of soldering flux to the chip’s 8 pins if you wish. Set the heat gun or air station to high temperature and airflow settings. With one hand, hold the air-generating tip half an inch from the chip for 10 to 15 seconds. With your other hand, gently pull away some of the heat from the chip and try to lift it with the tweezers. Do not tear the ROM chip off the PCB: it should come off without forcing it. Repeat this with the original ROM chip. Be sure to remember which side of the chip was facing up on the board. There is a dot on the chips and PCBs in case you forget which side was facing the board.
Next, align the ROM chip from the old board onto the new board. Apply heat for 10 to 12 seconds, remove the heat, and let the board cool. Make sure the ROM chip is firmly in place. You can now connect your hard drive and perform a data recovery.