Cause

TCR sensor fault (C-2411 - Yellow, C-2412 Magenta, C-2413 - Cyan, C-2414 Black)

Resolution

If value is 0 clean the connector on the back of the process unit as per the image below with a clean paintbrush..

Step 1.
Power the machine OFF from the main switch leaving the sub switch ON.
Turn main power switch ON while pressing the Utility/Counter key. Keep holding it till the comes up in Service mode.
-02 process adjustment
-06 recall standard data
-02 drum peculiarity
-06 toner revert all on (Keep running until all values are circa 1.26)
-02 gamma automatic adjust (wait for adjustment to complete)

Step 2.
-01 Machine Adjustment
-01 Printer Adjustment
-10 Colour Registration Adjustment (wait for adjustment to complete)
When completed exit out of service mode.