Oki ES3640MFP Service & Troubleshooting Manual page 52

Light Prints in All Colors
The overall image density is too light in all colors. If the image is light in only one color, see
"Light Print in Only One Color".
Initial Actions to Perform
Perform Initial Actions from
Verify the media used is supported by this printer.
Verify the media settings are correct at the Control Panel.
Print the PS Test and Demo pages to see if it is an application problem.
Run the color calibration routine
Areas of the Printer that Apply to Light Prints
1. Verify all packaging material has been removed form the toner cartridges
2. Remove the Imaging Units and the Transfer Unit and check for toner
contamination on the high voltage contacts. Are the contacts contaminated?
3. Are the LED Heads dirty? Clean the heads with a clean, lint-free cloth. Did this
correct the problem?
4. Are the wiring harnesses on the LED Heads undamaged, properly routed and
seated?
5. Inspect the high-voltage wiring harness. Reseat the wiring Harness. Did this
correct the problem?
Print Quality Troubleshooting Practices
Imaging Unit
LED Head
Transfer Unit
HVPS
Engine Control Board
Troubleshooting Steps Resolution
Yes – Go to Step 2
No - Remove packing material
Yes – Clean the contacts
No - Go to Step 3
Yes – Complete
No - Go to Step 4
Yes – Repair / Replace Harnesses
No - Go to Step 5
Yes – Complete
No - Replace in the following
order: Transfer Unit / LVPS /
Imaging Unit Sensor Board / HVPS
/ Engine Control PCB