How to Change The MacBook Serial on an Older MacBook With a CH341A Programmer

This guide will walk you through changing the serial number of your MacBook using a CH341A programmer.

1. Disassemble your MacBook and remove the motherboard from the housing.
2. Using hot air, remove the MacBook EFI IC from the motherboard.
3. Using hot air, mount the EFI to the a reader of your choice (See our products HERE)
4. Install the adaptor into the CH341A Programmer.
5. If you do not already have software for your CH341A programmer, you can download it HERE.
6. If you have no used he CH341A programmer with your PC before, then install the included driver (will be included in the zip folder of the above download).
7. Using a windows-based PC, open up the CH341A Programmer V1.01 software.
8. Click on the button labeled Auto Detect (25xx) towards the top of the program.
9. Select the chip version you are attempting to read.
10. Click on the button labeled Read towards the top of the program.
11. Once the read is complete, click on the button labeled Save towards the top of the program. Be sure to name the file something easy to remember with the original serial number somewhere in the file name.
12. Close the Program, then reopen it (due to software bug). Repeat steps 7 & 8.
13. Click open, then select the file you created in step 11.
14. Click on the Edit menu item list, then select Find. Search for the string SSN. If the first result does not look similar to what is pictured, then keep pressing F3 until you find the correct SSN reference.
15. At this point, you should see your serial number. You can now change this to any serial number you wish
16. Once you’ve change the serial number, click on the Save button. Be sure to name the file something easy to remember with the new serial number somewhere in the file name
17. Click on the button labeled Auto towards the top of the program. You will get a prompt asking “Are you sure to program the chip automatically?” Select Yes to proceed. This will erase the EFI ROM IC, write the new EFI ROM image, then verify the EFI ROM based on the contents of the ROM file.
18. Once finished, you should get a prompt stating “The chip as been verified successfully. All content are the same.” Click on the OK button
19. Remove the programmer and adaptor. Remove the EFI ROM IC from the Adaptor and re-solder the EFI ROM IC back onto the MacBook motherboard.
20. Load/Install macOS and confirm the serial number is equal to what you typed in the CH341A Programming tool

While this guide uses the CH341A programmer, it can be universally applied to other software as long as you have a basic understanding of SPI Flash programming. AsProgrammer is another tool you can use to work with the T2 ROM IC without issue.