Canon LBP-CX Series Service Manual page 176

Cause Step
Check Result
Measure
DC power supply 4 Is +24VDC supplied between J401-l
NO Check whether +24VDC is supplied
&
main motor and J401-2 (GND) on the scanner
between 1208-9 and J208-8 (GND)
driver PCB driver
&
scanner motor unit?
on the DC controller PCB. If
+24VDC is not supplied there, check
J502 on the DC power supply
&
main motor driver PCB and
1208 for poor contact. If contact
is good, replace the DC power
supply & main motor driver PCB.
DC controller PCB 5
Does the voltage between J206-4 NO
Replace the DC controller PCB.
Scanner driver PCB (SCNON) and J206-2 (GND) on the
Replace the scanner unit. (See IV.
DC controller PCB vary from about
+7DC to about OV when the
A. in Chapter4.)
same procedure as in step 2 is
If this does not correct the
performed?
problem, go to step 6.
Scanner driver PCB,
6
Does the voltage between J401-3 YES Replace the DC controller PCB.
DC controller PCB,
(SCNRDY) and J401-2 (GND) in
Is the problem solved? If not, put the
the scanner driver PCB of the
old PCB back in the printer ahd
scanner unit vary from about
replace the scanner unit. (See IV.
+3VDC to about OV a few
A. in Ch. 4.)
minutes after the same procedure
NO
Replace the scanner unit. (See IV.
as in step 2 is performed?
A. in Ch. 4.)
j
M-13. j Heater malfunction. j
Cause
Step
Check Result
Measure
Fixing temper-
1
Switch the power ON and wait one
NO
Go to M-4.
ature control minute. Open the upper half of the
printer. Take off the upper cover of
the fixing assembly. Has the tern-
perature of the upper roller in-
creased?
DC power supply 2 Is the voltage between J204-l and
NO
Check whether the voltage between
&
main motor
J204-4 (GND) from +20VDC to
1208-2 and J208-3 (GND) is from
driver PCB +30VDC, and +SVDC between
+20VDC to +30VDC, and +SDC
J204-5 and J204-4 (GND) in the
between J208-7 and J208-6 (GND).
laser unit?
If not, check the wiring between
J502 on the power supply
&
main
motor driver PCB and J208 for poor
contact. If contact is good, replace
the DC power supply
&
main motor
driver PCB.
COPYRIGHT
©
BY CANON INC. CANON LBP·CX SERIES REV.2 JULY 1985 PRINTED IN JAPAN (IMPRIME AU JAPOllJ
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