Oki MC160n - Manual (Page 165)

165 Replacing Consumables
Note
Do not touch the wires and flat cable
shown in the illustration.
"
The machine must complete a calibration cycle (less than 2 minutes)
after the imaging cartridge has been replaced. If you open the scanner
unit or front cover before the machine is reset, the calibration stops,
then starts over again after the cover is closed.