Foggy Background Or Rough Image - Minolta Di152 Service Manual

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Foggy background or rough image

Section Step
Output 1 Image condition changes after "ID
system Adjustment" and "VG Adjustment" have
been made.
2 PC Drum surface and the areas in con-
tact with Ds Collars are dirty with foreign
matter, or deformed or worn.
3 Main Erase (LA1) is dirty.
4 Grid bias contact is dirty, scratchy,
deformed, worn, or damaged.
5 ATDC Sensor (UN1) is dirty with foreign
matter (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
7 The following voltage is supplied from
the Master Board (copier: PWB-A).
<Check Procedure>
Check voltage across a Master Board
pin and GND when the Start key is
pressed.
• Voltage across PJ8A-8 and GND
DC14 V in standby state
DC0 V when Start key is pressed
Input 1 Original Glass is dirty.
system
2 Scanner mirrors are dirty.
3 Exposure Lamp (LA2) is dirty.
4 CCD Unit lens and CCD surface are
dirty.
<Check Procedure>
Remove lens cover to check for possible
contamination.
Check
T-49
Result Action
YES • Readjust.
For more details, see
SWITCHES ON PWBs/
TECH. REP. SET-
TINGS.
YES • Clean or change.
YES • Clean.
YES • Clean, correct, or
change.
YES • Clean.
NO • Change ATDC Sensor
(UN1) and then change
developer.
YES • Adjust Db.
For details, see DIS/
REASSEMBLY,
ADJUSTMENT.
• Change Main Erase
(LA1).
• Change PC Drum.
• Change IU.
• Change High Voltage
Unit (HV1).
NO • Change Master Board
(copier: PWB-A).
YES • Clean.
YES • Clean.
YES • Clean.
YES • Clean.