Cause

Gamma correction abnormality

Resolution

Please look at the video link and then complete the steps below.

Watch Video Here

Then run toner density revert...

1. Power the machine OFF from the main switch leaving the sub switch ON.
2. Turn main power switch ON while pressing the Utility/Counter key. Keep holding it till the comes up in Service mode.
3. Select process adj
4. Select drum peculiarity
5. Select toner density revert - run that routine.
6. Press the [Return] key, which is displayed on the touchscreen.
7. Exit Service mode to return to normal operation

And then finally gamma automatic adjustment,..

1. -02 process adjustment
2. -06 recall standard data
3. -02 drum peculiarity
4. -02 gamma automatic adjust
5. Run this procedure.
6. Exit Service mode to return to normal operation