Cause

Gamma correction abnormality, the drum potential sensor (5501/6501) TCR sensor (6000/7000) for yellow (C-2811), magenta (C-2812), cyan (C-2813) or black (C-2814) may have a film of toner dust on it affecting sensitivity

Resolution

Clean the drum potential sensor as per the error code and then follow the procedure for running toner density revert and gamma correction.

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. -02 Select process adj
4. -02 Select drum peculiarity
5. -06 Select toner density revert - select "All On" button run that routine.
    for 5500/6500 - should be under sensor output check - density return mode
    max density sensor (All values should be in 1.26 range, so keep pressing the start button until you get the values near)
6. Press the [Return] key, which is displayed on the touchscreen.
7. Exit Service mode to return to normal operation

Gamma Automatic Adjustment

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. -02 process adjustment
4. -06 recall standard data
5. -02 drum peculiarity
6. -02 gamma automatic adjust (wait for procedure to complete)

Exit out of service mode and go into adjustment at the bottom of the screen.

1. -03 execute adjust operation
2. Select toner refresh mode press ok.