Oki ES3640MFP Service & Troubleshooting Manual page 69

Scan Direction Dark Streaks
There are dark lines running parallel with the leading edge of the print.
Initial Actions:
Perform Initial Actions from
Areas of the Printer that Apply to Scan Direction Dark Streaks
1. Print the Color Test Pages. Does the problem occur in one primary color?
2. Inspect the Transfer Unit. Has the cleaning blade flipped or failing to clean the
Transfer Unit?
3. Inspect the Fuser rollers for contamination. Is the Fuser contaminated?
4. Print a test print Did the test pattern print correctly?
Print Quality Troubleshooting Practices
Imaging Unit
Transfer Unit belt
Troubleshooting Steps Resolution
Yes – Replace the Imaging Unit
of the defective color.
No – Go to Step 2.
Yes – Replace the Transfer Unit.
No - Go to Step 3.
Yes – Replace the Fuser.
No - Go to Step 4.
Yes – Replace the Fiery Control
Board
No - Replace Engine Control
Board