IBM 1800409-001A - Manual (Page 44)

CAUTION: The same color developer and toner cartridges must
always be loaded in the same place on the printer. To prevent
accidental mixing of colors, each toner cartridge has pins that are
keyed to fit only the developer cartridge of the corresponding color.
Never force a toner cartridge onto the wrong developer cartridge.
This can damage the cartridges and the printer.
NOTE: A developer cartridge must be installed before the toner
cartridge of the same color.
1. Remove the developer cartridge from its protective bag,
starting with the black cartridge. (The developer cartridges are
color-coded on their tops.)
Chapter 2
2 - 1 2 I n i t i a l P r i n t e r S e t u p