Low Image Density - Minolta Di152 Service Manual

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Low image density

Section Step
Output 1 Image density changes after "Toner
system Replenisher" has been run.
• "Toner Replenisher" of Utility
2 Image density changes after "ID Adjust-
ment" and "VG Adjustment" have been
made.
3 Image transfer current contact is dirty,
folded, or bent.
4 Developing bias contact is dirty, folded,
or bent.
5 High Voltage Unit (HV1) connectors
CN1HV1 and CN2HV1 are loose.
6 ATDC Sensor (UN1) is dirty with foreign
matter (such as paper dust) other than
developer.
7 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
8 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
Check
T-47
Result Action
YES • Replenish the supply of
toner using "Toner
Replenisher."
YES • Readjust.
For more details, see
SWITCHES ON PWBs/
TECH. REP. SET-
TINGS.
YES • Clean, correct, or
change.
YES • Clean, correct, or
change.
YES • Reconnect.
YES • Clean.
NO • Change ATDC Sensor
(UN1) and then change
developer.
YES • Change IU.
• Change High Voltage
Unit (HV1).
NO • Change Master Board
(copier: PWB-A).