Faint printing on C6500

[adeyemi]

C6500 prints faintly for all four colors. Half tone test pattern 53 at 255 for each colour is not as rich for each of them as should be. Problem not from controller because IC-408 attached prints well on another machine.

[dljorg]

Hello -

Transfer belt is mounted correctly? Black disk on the side frame of the transfer belt unit should have its cut out pointed down when the belt is installed.

Lower transfer roller next to the fuser has its bearings in place and moves up and down correctly? - try by hand and then take a look at the gears on the lift motor.

Question would be are there any error codes associated with this? Should be either for toner or charge.

Things to check:
In sensor output check in service mode test the toner density sensors. Use all on when you get to the screen. Normal reading is about 130 give or take. Higher number near 200 means the dev unit is undertoned. If all of the color channels are undertoned the best thing to do is replace the developer and readjust the TCR sensor like at PM time. If all colors are undertoned there a a number of possibilities, door microswitch being my favorite but again should be a code.

In sensor output check in service mode test the Drum Surface Potential. Vo depends on drum age but should be about 160 to 200. Vi is for the uncharged drum and should be about 20. If they are way out try running the Autogamma adjustment in Drum Pecularity and if you get lucky they will snap back.

Have never seen a bad transfer or charge power supply on these do an all colors weak thing but theoretically its possible.

Good Luck
dljorg