Dc Power Is Absent - Canon NP6045 Service Manual

CHAPTER 10 TROUBLESHOOTING

29. DC power is absent.

Cause Step
AC power
supply
Wiring, DC load
DC power
supply PCB
10-88
COPYRIGHT © 1997 CANON INC.
Checks
1 Is the rated voltage present
between J301-1 and J301-5 and
between J301-3 and J301-5 and
between J302-1 and J302-3?
(J301 and J302 are in the DC
power supply unit.)
2 Is the fuse (FU51, FU1) on the DC
power supply PCB blown?
3 Turn OFF the power switch, and
disconnect the power plug; then,
connect the power plug about 1
min later. Is DC power supplied
when the power switch is turned
ON?
4 Turn OFF the power switch, and
disconnect all connectors J303,
J304, J305, J306, J308, J309, and
J311 from the DC power supply
PCB; turn ON the power switch,
and measure the voltage between
the terminals shown in Table.
Connector Pin No.
1
J303 2
3
2
J304
4
1
3
J305
5
7
J306 1
1
J308 3
5
1
J309
3
1
J311
2
However, the above assumes that
the inaccuracy of the AC input is
±10%.
YES/NO
Output Remarks
38VU +10%,-7%
38VU +10%,-7%
38VU +10%,-7%
24VR ±2%
24VU +10%,-7%
24VU +10%,-7%
24VR ±2%
5VR ±4%
12VU +10%,-7%
24VU +10%,-7%
24VU +10%,-7%
24VA +10%,-20%
38VU +10%,-7%
24VU +10%,-7%
24VU2 +10%,-7%
24VA2 +10%,-7%
38VU +10%,-7%
CANON NP6045 REV. 1 MAR. 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
Action
NO See "AC power is
absent."
YES Remove the cause, and
replace the fuse.
YES End.
YES Turn OFF the power
switch, and connect one
of the connectors you
have disconnected.
Connect the connector,
and turn ON the power.
Repeat this procedure to
find out the connector
that activates the protec-
tion circuit, and check
the wiring and DC loads
from that connector.
NO Replace the DC power
supply. See "AC power
is absent."