Canon NP6251, Руководство по обслуживанию

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F. Electrical System
1. When Replacing the DC Controller PCB
1) Install the new DC controller PCB.
2) Press the service mode switch with a clip over the cover.
3) Select the following in service mode (
):
‘RAM_INIT’:0
←
(
]
: START)
4) Press the user mode key
]
.
5) Execute AE adjustment.
6) Enter the values indicated on the label attached behind the front door.
7) Enter the settings suited to the user in service mode (
).
8) Press the Reset key twice.
2. Checking the Surface Potential Control System
a. Outline
If an image fault occurs, try to find out whether the problem is in the latent image
formation block (including the photosensitive drum and the potential control system) or
the developing/transfer system, requiring a check on the surface potential. (You may
check the surface potential in service mode.)
b. Disabling the Auto Control Mechanism
You may disable the auto control mechanism to find out whether the corona current
control, lamp intensity control, or developing bias control is faulty or not (non-auto control
mode).
Further, as a temporary remedy, you may use non-auto control mode against a fault
in the auto control mechanism.
In auto control mode, all outputs are set to default settings.
q
Steps
1) Select ‘PO_CONT’ in service mode ( ).
2) Check to make sure that the indication on the display is as follows:
NIP : 0
←
(
]
: START)
PO_CONT : 0
←
(
]
: START)
Changes to ‘1’.
]
4
]
]
5
]
]
4
]
COPYRIGHT © 1997 CANON INC. CANON NP6350/NP6251 REV. 0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
CHAPTER 11 TROUBLESHOOTING
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