When a serial number really isn’t

I’m installing a new hard drive in my wife’s PC, to replace the 5+ year-old that has died. I dutifully noted the part number and serial number for warranty registration purposes, since this drive has a 5-year warranty itself. Calling it a “serial number” may be stretching it, however: Y2CJECZE.
Can you call a string a “serial number” when only one of the characters qualifies as a numerical value?