Star Micronics LS-5 SERIES Technical Manual page 122

TROUBLESHOOTING
P-2. Blank
Print sample
Step
1 (Defective grounding of the drum)
Has the drum of the EPX toner cartridge been grounded
securely?
[Grounding Route]
↔
Drum Pin of drum shaft
harness assy HVPS
2 (Obstruction of the laser beam path)
Is there any foreign matter or grime in the path of the laser beam
between the ROS assy and the drum?
3 (Faulty HVPS DB)
Is the output of the HVPS DB normal?
4 (Faulty drive assy)
Are the gears of the drive assy which conveys drive to the EPX
toner cartridge rotating normally?
5 (Faulty BTR assy)
Is there any foreign matter or grime on the BTR of the BTR
assy?
6 (Faulty image transfer)
Is the toner image on the drum transferred correctly to the
paper?
* Try turning off the power at the point in printing when you
think the image is being transferred to the paper, and check
the image on the drum.
7 (Faulty EPX toner cartridge)
Does the problem stop occurring when the EPX toner cartridge
is replaced with a new one?
Blank print (white paper)
(This refers to printing in which no image is printed at all, and the paper is left
completely white.)
Check parts with different specifications for problems with usage, defective
installation, breakage, deformation, and adhesion of grime or foreign matter.
• Main parts to be checked:
(1) EPX toner cartridge, (2) HVPS, (3) MCU PCB, (4) Earth plate assy
(5) BTR assy, (6) Trans. chute assy, (7) Wire assy TR
(8) Harness assy HVPS, (9) LVPS assy, (10) ROS assy
Check
↔
earth plate assy
↔ ↔
MCU PCB LVPS assy
– 118 –
Symptom
Initial check
Measure (if abnormal)
Make sure there is good conductivity
along the grounding route.
↔ ↔
HVPS
Remove any foreign matter or grime
obstructing the path of the laser beam
from the ROS assy to the drum.
To section 3-19
To section 3-17
Replace BTR assy.
To section 3-20
Replace EPX toner cartridge.