How to fix bricked Seagate hard disk (with illustrations)

BIOS showing hard disk status

This is an image based tutorial that will show step by step on how to fix bricked Seagate hard disk (model ST3500320AS). This model ST3500320AS is a 500GB hard disk but it has known busy bug or BSY error. If the hard disk is hit by this bug, its size will be detected 0 bytes by BIOS. Disclaimer: webfoobar assumes no responsibility for any data loss or permanent damage executing the following tutorial steps (use at your own risk).


  1. 1 piece USB to UART connectivity bridge (this tutorial uses Nokia CA42 cable) with driver
  2. 5 pieces wafer connector
  3. 1 piece 2 x AA battery holder
  4. 2 pieces AA battery
  5. VOM or Multitester
  6. COM port terminal software (this tutorial uses PuTTY)

 Cable Construction Steps:

Nokia CA42 Cable

  • Cut the cable into two. We only need the part with USB plug. Therefore, it is logical to cut the wire with USB plug more longer. We will use the other half of the cable in identifying its pinouts in the next step.
  • The cable's wire color may vary in different manufacturer so identify the pinouts of your cable using VOM. I have identified mine as (be sure to add label on each wire):
    Nokia CA42 Pinout
  • Connect the wafer connector at the tip of the cable's wires (the one with USB):
    Nokia CA42 with wafer connector
  • For improvement, add shrinkable tube:
    Nokia CA42 with shrinkable tube
  • Connect the battery holder:
    Nokia CA42 with battery holder

Prepare the Hard disk:

Seagate Hard disk

  • Remove the Printed Circuit Board (PCB):
    Hard disk PCB
  • Remember the position of the PCB on the hard disk and where the screws are connected:
    Disassembled hard disk
  • Put an insulation (something like thick paper or calling card) between the PCB and the connector of the hard disk:
    Hard disk connector to its PCB
    Thick paper on top of hard disk connector
  • Return the PCB on the hard disk with the paper insulating the PCB and hard disk connector then reconnect the screw to temporarily hold the PCB on hard disk:
    PCB connected on hard disk with paper
  • Remove the hard disk jumper:
    Hard disk jumper
  • Connect the customized cable to the hard disk. Here's the pinout of the hard disk:
    Hard disk pinout
  • Connect the SATA power to the hard disk and wait until the motor stops:
    SATA power and CA-45 connected

Driver Installation: 

Nokia CA42 Driver

  • Attach the two double A batteries. Connect the cable to the computer. The CD driver may not be needed, my Windows download it automatically:
    Driver installation 1
  • After it downloads, Windows will try to install it:
    Driver installation 2
    Driver installation 3
  • New window will appear at the back and click that window:
    Driver installation 4
  • Click "Finish" button
    Driver installation 5
  • Message should appear at your taskbar that the driver has been installed:
    Driver installation 6
  • It is important to identify the port number of your installed USB to UART connectivity bridge. Open your "Control Panel" and double click "System":
    Driver Installation 7
  • A window will popup. Click "Device Manager":
    Driver installation 8
  • Click "Modems":
    Driver installation 9
  • Double click "Nokia CA-42 USB Modem":
    Driver installation 10
  • A new window will popup. Click "Modem" tab:
    Driver installation 11
  • Take note of the port number (mine is COM7):
    Driver installation 12

Communicating with hard disk:

Note: Make sure to follow the upper and lower case when typing on terminal.

  • Open PuTTY terminal. From the "Category" column, select "Serial". Input the port number of your USB to UART connectivity bridge cable to "Serial line to connect to" field (in my case, I entered COM7), 38400 to "Speed (baud)" field, 8 to "Data bits", 1 to "Stop bits", select "None" from "Parity" dropdown menu and also "None" for "Flow control". Click "Open" button:
    Setup PuTTY serial options
  • Hit the CTRL+Z keys and it should display a prompt saying F3 T>:
    Communicating with hard disk step 2

  • Type /2 and hit Enter:
    Communicating with hard disk step 3

  • Type Z and hit Enter:
    Communicating with hard disk step 4

  • Remove the inserted paper from the hard disk and tighten up all its screws:
    Communicating with hard disk step 5

  • Type U and hit Enter:
    Communicating with hard disk step 6
    The next commands are just for checking if everything are ok (Note: this test only works for 500GB 7200.11 hard disks with firmware SD15. Type / and hit Enter:
    Communicating with hard disk step 7
    Type F712 and hit Enter:
    Communicating with hard disk step 8
    Type F,,22 and hit Enter:
    Communicating with hard disk step 9
    Type F712 and hit Enter:
    Communicating with hard disk step 10
    This is the end of the checking part. The next steps should be performed.

  • Type /1 and hit Enter:
    Communicating with hard disk step 11

  • Type N1 and hit Enter:
    Communicating with hard disk step 12

  • Type / and hit Enter:
    Communicating with hard disk step 13
    The terminal will clear and it should display:
    Communicating with hard disk step 14

  • Unplug the SATA power of the hard disk, reconnect it and wait for 20 seconds. Type m0,2,2,0,0,0,0,22 and hit Enter:
    Communicating with hard disk step 15

  • Remove the SATA power and the customized cable from the hard disk. Shutdown your computer, install the hard disk to your computer and reboot. The hard disk should be working by now and be sure to update the firmware of your hard disk ASAP.

If you prefer to buy instead of building one for yourself, this tool: Complete Kit Seagate Barracuda 7200.11 Firmware Repair Fix Tool USB Power might help you.


The 3.3 battery's positive terminal is connected on pin 2 and the negative terminal on pin 6 (please see illustration bellow):
Nokia CA42 Pinout


To add the battery:

  1. Cut the cable into two (we only need the part with USB plug).
  2. Use the other half of the cable with CA42 plug to identify its pinouts using VOM because cable's wire color may vary in different manufacturer. I have identified mine as:Nokia CA42 Pinout
    Note: be sure to add label on each wire.
  3. Solder the battery holder on the cable with USB plug attaching the wire based on the pinouts you have identified. In my case, using the image above I attached the red wire of the battery holder on number 2 (3.3 volts pin) and the black wire of the battery holder on number 6 (Ground pin).

Hi, I have a drive 7200.11 that failed when updating the firmware. Could I use this method to fix it?

Thanks, Hernan

Hi, the instructions presented above is for fixing busy bug or BSY error of Seagate hard disk. Anyway, if your hard disk is already unusable, you can always try but at your own risk (expect the worst: you might break your hard disk more). Good luck.

When typing, m0,2,2,0,0,0,0,22 the prompt says format user partition: Is this erasing data??

Will this tutorial wipe the drive of all it's data?

My colleague claimed he was able to retrieve data in his hard disk. But in my case, the data were gone. Anyway, the data on my hard disk doesn't matter to me, I care only of fixing the hard disk. Follow the tutorial at your own risk.

You can also use a Prolific PL2303 USB to Serial (TTL) Module/Adapter and some jumpers. Lots easier than the old Nokia cable.

I'd long since given up on getting the data back from my 7200.11 until I saw this fix.

Thank you very much for this explanation. If you allow me, I have a question. I cannot find a Nokia cable. Can I use any other USB cable like those used in modern phones, or can I use an rs.232 connection? Please answer me, with pictures.. and how to determine the tx. Rx, do we connect the Rx from the USB to the Rx of the hard disk or connect the RX to the TX? Thank you...

Thank you for the explanation, sir. Another question regarding the batteries. Can we put 5 volt batteries or exclusively 1.2 volt batteries in series?
And for TX .RX Pinouts ..?
Thank you for your attention

have a nice day . Please answer. I could not get a ca-42 cable. Can I use DUK 2 instead.......? Secondly.....Can this be applied to Windows 7.64bit? I tried and it did not work on Windows 7 - 64bit. There is always no response on putty, even though the port com is open. And everything, but there is no response from the HDD.. Thank you....

Try experimenting by connecting a device, such as a mobile phone, to the other end of the cable and changing the baud rate until you receive a response in Putty.

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