No Image Appears (Entirely Black) - Kyocera TASKalfa 220 Service Manual

2KL/2KK
(1) No image appears (entirely white).
Copy example
No trans-
fer charg-
ing.
No LSU
laser is
output.
No devel-
oping bias
output.

(2) No image appears (entirely black).

Copy example
No main
charging.
Exposure
lamp fails
to light.
1-4-22
Causes
The connector terminals
of the high voltage PWB
make poor contact.
Defective high voltage
PWB.
Defective main/engine
PWB.
Defective laser scanner
unit.
Defective main/engine
PWB.
The connector terminals
of the high voltage PWB
make poor contact.
Defective high voltage
PWB.
Defective engine PWB.
Causes
Broken main charger
wire.
Leaking main charger
housing.
The connector terminals
of the high voltage PWB
make poor contact.
Defective high voltage
PWB.
Defective main/engine
PWB.
Poor contact in the expo-
sure lamp connector ter-
minals.
Defective inverter PWB.
Defective main/engine
PWB.
Check procedures/corrective measures
Reinsert the connector. Also check for continuity within the
connector cable. If none, remedy or replace the cable.
Check if transfer charging takes place when CN1-4 on the
high voltage PWB goes low while maintenance item U101 is
run. If not, replace the high voltage PWB.
Check if YC8-4 on the main/engine PWB goes low when
maintenance item U101 is run. If not, replace the engine
PWB.
Replace the laser scanner unit (see page 1-5-28).
Check if YC35-5 on the main/engine PWB goes low when
maintenance item U100 is run. If not, replace the main/
engine PWB.
Reinsert the connector. Also check for continuity within the
connector cable. If none, remedy or replace the cable.
Check if developing bias is output when CN1-9 on the high
voltage PWB goes low while maintenance item U101 is run.
If not, replace the high voltage PWB.
Check if YC8-9 on the engine PWB goes low when mainte-
nance item U101 is run. If not, replace the engine PWB.
Check procedures/corrective measures
Replace the main charger unit (see page 1-5-36).
Clean the main charger wire and grid.
Reinsert the connector. Also check for continuity within the
connector cable. If none, remedy or replace the cable.
Check if main charging takes place when CN1-7 on the high
voltage PWB goes low while maintenance item U100 is run.
If not, replace the high voltage PWB.
Check if YC8-7 on the main/engine PWB goes low when
maintenance item U100 is run. If not, replace the main/
engine PWB.
Reinsert the connector. Also check for continuity within the
connector cable. If none, remedy or replace the cable.
Check if the exposure lamp lights when YC1-3 on the
inverter PWB goes low while maintenance item U061 is run.
If not, replace the inverter PWB.
Check if YC16-4 on the main/engine PWB goes low when
maintenance item U061 is run. If not, replace the main/
engine PWB.