Canon NP6251 Service Manual page 623

CHAPTER 11 TROUBLESHOOTING
12. E030 (The total copy counter fails to turn on.)
Cause Step
Total copy
counter
Total copy
counter
DC controller
PCB
13. E031 (The option counter has an open circuit.)
Cause Step
Option counter
Total copy
counter
DC controller
PCB
11-92
COPYRIGHT © 1997 CANON INC.
Checks
1 Turn off the power switch, and
disconnect J104 from the DC
controller. Set the meter to the
1K range, and measure the
resistance between J104B-2 and
J104B-1. Is it about 500 ?
2 Connect J104 to the DC controller
PCB, and turn on the power
switch. Set the meter to the
30VDC range, and measure the
voltage between J104B-2 (+) and
J104A-6 (–) on the DC controller
PCB. When the Copy Start key is
pressed, does it change from
about 24 V to about 0 V and then
to 24 V?
Checks
1 Turn off the power switch, and
disconnect J104 from the DC
controller. Set the meter to the
1K range, and measure the
resistance between J104B-6 and
J104B-7. Is it about 500 ?
2 Connect J104 to the DC controller
PCB, and turn on the power
switch. Set the meter to the
30VDC range, and measure the
voltage between J104B-6 (+) and
J104A-6 (–) on the DC controller
PCB. Does it change from about
24 V to about 0 V and then to
about 24 V?
YES/NO
NO
YES
NO
YES/NO
NO
YES
NO
CANON NP6350/NP6251 REV. 0 JULY 1997 PRINTED IN JAPAN (IMPRIME AU JAPON)
Action
Check the wiring from
the DC controller PCB to
the total copy counter; if
normal, replace the total
copy counter.
Replace the total copy
counter.
Replace the DC
controller PCB.
Action
Check the wiring from
the DC controller PCB to
the total copy counter; if
normal, replace the total
copy counter.
Replace the total copy
counter.
Replace the DC
controller PCB.