DRUM ERROR KONICA C224 554
A persistent drum unit error on a Konica Minolta bizhub C224, C364, or C554 is usually caused by dirty electrical contacts, a spent reset chip, or an expired unit. Open the front door, lower the internal levers, and slide out the affected drum unit (Cyan, Magenta, Yellow, or Black). Wipe the gold-plated electrical contact points on both the back of the drum and inside the machine chassis with a dry, lint-free cloth to clear stray toner dust. If the drum has exceeded its life limit, you can bypass the error by replacing the reset chip or installing a brand-new drum unit. Reinsert the unit securely and reboot the machine to reset the error code.