User manual

95.08.23.11.30
Color LaserWriter 12/600 PS Basics & Theory 1–118
Fuser Error B:
Fuser Safety
Circuit Detects
Error
The fuser heater safety circuit in the power supply unit will shut off the
power supplied to the fuser heater if the fuser temperature rises abnor-
mally.
Safety
Circuit IC
Z4
Z5
Z5
Z5
Z5
Fuser Heater
Safety Circuit
Fuser Assembly
Abnormality
Detection Circuit
RL
Q805
+24V
+5V
13
10
11
14
2
5
4
1
7
6
+5V
FXSTS
SFSNS
+5V
+5V
8
9
10
/FXROF
IC101
THI
THSEL
TH
12
6
2
5
14
IC102
JP1
JP2
T2
TP1
TP2
CPU
/FXUON
/FXLON
Fuser Heater
Drive Circuit
/FXENB
Power Supply
Fuser Assembly
Lower
Fuser
Roller
Upper
Fuser
Roller
TH
Thermistor
Mechanical
Controller
Board
DC
Controller
Board