The Copier Does Not Turn On - Minolta Di350 Service Manual

FrameMaker Ver.5.5E(PC) Di350 TROUBLESHOOTING
98.12.09

(7) The Copier Does not Turn ON.

Power Switch S1
Side Cover Interlock Switch 1 S2
Power Supply Unit 1 PU1
Power Supply Unit 2 PU2
Symptom Step
Power 1
does not
turn ON.
2
3
4
5
6
7
8
9
The con- 1
trol panel
indicates
nothing.
2
Relevant Electrical Parts
Check Item
Is there an AC power supply
voltage across PJ1PU1-1 and 3
on PU1 when S1 is turned ON?
Is the voltage across PJ5PU1-
10 and GND DC5V when S1 is
turned ON?
Is the voltage across PJ5PU1-4
and GND DC24V when S1 is
turned ON?
Is the voltage across PJ5PU1-3
and GND DC24V when S1 is
turned ON?
Does the voltage across the S2
connector (yellow) and GND
change from DC0V to DC24V
when S2 is turned ON?
Is the voltage across PJ7PU1-9
on PU1 and GND DC3.3V?
Is the voltage across CN1PU2-1
on PU2 and GND DC24V?
Is the voltage across CN28UN2-
8 on UN2 and GND DC-12V?
Is the voltage across CN28UN2-
7 on UN2 and GND DC12V?
Is DC24V being output from
UN2 to UN1?
Disconnect CN1UN1 of UN1
and check to see if the voltage
across CN1UN1-1 on the har-
ness side and GND is DC24V.
Is DC5V being output from UN2
to UN1?
Disconnect CN1UN1 of UN1
and check to see if the voltage
across CN1UN1-28 on the har-
ness side and GND, and across
CN1UN1-29 and GND, is DC5V.
Master Board PWB-A
Control Panel UN1
MFB Board UN2
Result
NO
YES Check the fuse on PWB-A.
NO
NO
NO
NO
NO
NO
NO
YES Change PWB-A.
NO
NO
YES Change UN1.
NO
T-42
Action
Check S1, PU1 fuse, and
power supply voltage.
Change PU1.
Change PU1.
Change PU1.
Check S2.
Change PU1.
Change PU1.
Change PU2.
Change PU2.
Change UN2.
Change UN2.