Canon 1000 Service Manual page 136

3. OPERATION AND TIMING
a. Procedure for Drum Surface Potential
Control at Power-On
Step Drum rotation
1
1st rotation
2
3
2nd rotation
4
5
3rd rotation
6
7
4th rotation
8
9 Computes based on measurements
b. Procedure for Computation and Associated Detail Codes
Step Checks
Measured value
1
check
VD/VL check
(computed
based on
2
measured
value)
3-92
COPYRIGHT © 2001 CANON INC.
Grid output
Vg1 (-300V) output
Vg2 (-700V) output
Table 3-502
Detail code Description of detail code
Difference of the measured value
xx01
of VD1 is 30 V or more
Difference of the measured value
xx02
of VD2 is 30 V or more
Difference of the measured value
xx03
of VL1 is 30 V or more
Difference of the measured value
xx04
of VL2 is 30 V or more
VD1 is 500 V or more and, in
xx10
addition, VD2 is 900 V or more
VD1 is 900 V or more and, in
xx11
addition, VD2 is 900 V or more
VD1 is 200 V or less and, in
xx12
addition, VD2 is 600 V or less
VD1 is 150 V or less and, in
xx13
addition, VD2 is 300 V or less
VD1 and VD2 both are 150 V or
xx14
less
VD1, VD2, VL1, and VL2 are all
xx15
10 V or less
Difference between VD1 and VL1
is 20 V or less and, in addition,
VD1 is 200 V; or, difference
xx16
between VD2 and VL2 is 20 V or
less and, in addition VD1 is 600
V or more
VL1 is 200 V or more and VL2 is
xx17
400 V or more
Table 3-503
CANON CLC1000/1000S/3100 REV.2 MAY 2001 PRINTED IN JAPAN (IMPRIME AU JAPON)
Laser output
Measures V
V output
FF
Measures V
Measures V
V output
00
Measures V
Measures V
V output
FF
Measures V
Measures V
V output
00
Measures V
Possible cause
Potential circuit PCB (faulty)
DC controller PCB (faulty)
Pre-exposure lamp (faulty)
Pre-primary, primary charging
assembly (faulty)
HV2 PCB (faulty)
Primary charging assembly (faulty)
HV2 PCB (faulty)
Laser power adjustment (faulty)
Laser unit (faulty)
Video controller PCB (faulty)
Primary charging assembly (faulty)
HV2 PCB (faulty)
Potential control PCB (faulty)
Scanner (faulty)
Laser unit (faulty)
Video controller PCB (faulty)
Laser (fails to emit a beam)
Laser unit (faulty)
Video controller PCB (faulty)
Laser power adjustment (faulty)
Intensity at VFF (too high)
1'
L
2'
L
1'
D
2'
D
1
L
2
L
1
D
2
D