M-5. Cannot Feed Paper Manually - Canon LBP-CX Series Service Manual

Cause
Step
Check
'Result
Measure
Thermistor
2
Unplug J2 l 2 on the DC controller
NO
Check the wiring between thermistor
PCB. Measure the thermistor
TH 1 in the fixing assembly and the
resistance between J2 l 2-4 and
DC controller PCB.
If
it is normal,
J212-5 (connector cable attached).
replace the thermistor. If the
Is it 100kil-400kil (at normal
thermistor resistance reaches the
temperature)?
specified value, proceed to step 3.
After measurement, plug in J2 l 2
on the DC controller PCB.
DC controller PCB
3
Does the voltage between Jl 04-1
NO
Check the wirjng between 1212 on
(FSRD) and J104-3 (+24V) on the
the DC controller PCB and J 104 on
fixing roller heater safety PCB go
the fixing roller heater safety PCB
from about +24V DC to about
for good contact. Repair any poor
+22VDC about one second after
contact. Is the problem solved?
the power is switched ON?
If not, replace the DC controller PCB.
AC driver PCB
4
Do the line voltages between the
NO Replace the AC controller PCB.
(fixing roller heater
specified connectors on the AC
Is the problem solved?
If
not, replace
safety PCB and AC
controller PCB vary as follows about
the fixing roller heater safety PCB.
controller PCB),
one second after the power
is
Is the problem solved? If
not,
triac Ql
switched ON?
reinstall the AC controller PCB and
•
from line voltage to OV AC
fixing roller heater safety PCB, and
between J105-7and1105-3
replace triac Q 1.
•
from OV AC to line voltage
between JlOl-1 and Jl 01-2
Note: If any fixing malfunction switch the printer OFF for about 10 minutes. If the printer is turned ON within
this period, the fixing roller heater will be turned OFF.
I
M-s.
I
Cannot feed paper manually
I
Cause Step
Check Result Measure
Operation t'lrror
1
Has the external device input a NO Input a manual paper feed command
manual paper feed command to from the external device to the
the printer? printer.
DC power supply 2 Is a pulse applied between J208-
NO
Check the wiring between J502 on
&
main motor
12 (TG) and J208-3 (GND) on the the DC power supply & main motor
driver PCB,
DC controller PCB? Check
it
with a
driver PCB and 1208.
main motor Logic Tone (CK-0400). If all are correctly connected, replace
the DC power supply & main motor
driver PCB or main motor M 1.
Pickup sensor 3 Does the voltage between J2 l 0-6
NO
Check J4 of the pickup sensor and
(PFS) and 1210-5 (GND) on the DC J2 l 0 on the DC controller PCB
controller PCB go from about
for poor contact. If it cannot be
OVDC to +5VDC when paper is
fixed, replace pickup sensor PS l.
set on the manual feed tray?
Faulty upper and
4
Does the upper manual pickup YES
Check the lower roller for wear and
lower manual roller descend and feed the paper
rotation. Check that the upper roller
pickup rollers about 8 seconds after the main presses the paper firmly.
motor begins rotating?
DC controller
5
Does the voltage between J2 l 0-4 NO
Replace the DC controller PCB.
PCB (MPUSD) on the DC controller
PCB and J210-5 (GND) go from
about +24VDC to aboutOVDC about
8 seconds after the main motor
begins rotating, and remain at OV for
about 1.5 seconds?
COPYRIGHT
©
BY CANON INC. CANON LBP.CX SERIES REY.2 JULY 1985 PRINTED IN JAPAN (IMPRIME AU JAPONJ
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