Service Checks
Fuser Service Check
FRU
1
• Heater
Lamp (H1)
• Thermostat
(S4)
• Power Unit
(PU1)
• Mechanical
Controller
Board
(PWB-A)
2
• Fuser
• Mechanical
Controller
Board
(PWB-A)
3
• Fuser
• Mechanical
Controller
Board
(PWB-A)
Action
Be sure the heater lamp (H1) lights up when the
power is turned on. (Open the rear door and acti-
vate the rear door interlock to see the fuser lamp.) If
the lamp does not light up, check for voltage
between CN2PU-1 and CN2PU-3 of the power unit
(PU1).
If there is voltage, replace the heater lamp (H1) or
the thermostat (S4).
If there is no voltage, replace the power unit (PU1)
or the mechanical controller board (PWB-A).
Check for voltage between CN9A-6 and CN9A-7 of
thermistor 1 (TH1). If there is no voltage, replace
the fuser.
If there is voltage, replace the mechanical controller
board (PWB-A).
Check for voltage between CN9A-8 and CN9A-9 of
thermistor 2 (TH2). If there is no voltage, replace
the fuser.
If there is voltage, replace the mechanical controller
board (PWB-A).
Diagnostic Information 2-33