Web/Javascript implementation kindly provided by James Portman at https://rovermems.com/.
Input hex strings only - 0-9 and A-F.
GM Code (8 digits without checksum):
Checksum: ?
SA Code (16 digits without checksum):
Checksum: ?
VN Code (10 digits without checksum):
Checksum: ?
Downloadable Excel Spreadsheet Version
Simple, free spreadsheet for calculating the checksums needed when entering new or updated ZCS codes on Rover 75 and MG ZT cars. The ZCS codes need to be updated whenever the vehicle configuration changes. In the past, people have had to pay significant sums of money for a one-off service to calculate the new checksums. With this simple spreadsheet you can calculate your own. Instructions and explanation included.