(11) Gradation Reproduction Failure - Minolta Di152 Service Manual

(11) Gradation reproduction failure

Section Step
Output 1 PC Drum is dirty.
system
2 Image Transfer Roller is dirty, scratchy,
deformed, worn, or damaged.
3 PH Unit connectors PJ12A and PJ13A are
loose.
4 PH window of PH Unit is dirty.
5 ATDC Sensor (UN1) is dirty with foreign mat-
ter (such as paper dust) other than developer.
6 The following voltages develop from the
ATDC Sensor (UN1).
<Check Procedure>
Check voltage across a Master Board pin and
GND when the Power Switch is turned ON.
• DC5.39 V to 8.15 V across PJ7A-8 and
GND
• DC1.41 V to 4.98 V across PJ7A-10 and
GND
Input 1 Original Glass is dirty, scratchy, worn, or
system damaged.
2 Shading sheet reading portion (the portion on
the backside of the Original Glass to which
Original Width Scale is affixed) is dirty.
3 Scanner mirrors are dirty, scratchy, or dam-
aged.
4 Exposure Lamp (LA2) is dirty.
5 CCD Unit lens and CCD surface are dirty or
scratchy.
<Check Procedure>
Remove lens cover to check for possible con-
tamination.
6 Exposure Lamp is abnormally lit (flickers or
abnormally dark) when the Start key is
pressed.
7 Inverter Board (copier: PU2) connector
CN1PU2 is loose.
8 CCD Board (copier: PWB-J) connector is
loose.
9 Control Board (copier: PWB-C) connector
PJ1A is loose.
Check
T-58
Result Action
YES • Clean.
YES • Clean or change.
YES • Reconnect.
YES • Clean.
YES • Clean.
NO • Change ATDC
Sensor (UN1) and
developer.
YES • Change Master
Board (copier:
PWB-A).
YES • Clean or change.
YES • Clean.
YES • Clean or change.
YES • Clean or change.
YES • Clean or change.
NO • Go to step 8.
YES • Reconnect.
NO • Change Exposure
Lamp (LA2).
YES • Reconnect.
YES • Reconnect.
NO • Change CCD Unit.
• Change Control
Board (copier:
PWB-C).