Print-Quality Troubleshooting 5-13
4
Check for any obstructions or debris in 
the laser beam path between the 
Laser Unit and the Imaging Unit.
Remove 
obstructions or 
debris.
Go to Step 5.
5
WARNING: Turn printer power Off and 
disconnect the AC power 
cord before proceeding 
with the following checks.
Check the affected colors connection 
between the HVPS and Housing 
Assembly Bias for continuity and 
damage.
JP101/102 <=>DA Y contact 
JP103/104 <=>DB M contact 
JP105/106 <=>DC C contact 
JP107/108 <=>DD K contact
Go to Step 6. Replace the Housing 
Assembly Bias 
 
(page 8-77).
6
Check the Developer Assembly gear 
train, PL8.1.1. Symptoms can be all 
colors, only one color, and only CMY 
color. IF CMY color only is bad (black 
is good), this is most likely the root 
cause.
Does the image quality improve?
Complete Go to Step 7.
7
Replace the affected color’s Developer 
Assembly.
Does the image quality improve?
Complete Go to Step 8.
8
Replace the Laser Unit (page 8-76).
Does the image quality improve?
Complete Replace the Engine 
Control Board 
 
(page 8-104).
Troubleshooting Procedure Table (Continued)
Step Actions and Questions Yes No