Fuser (Abnormal Temperature) Service Check (923) - Lexmark Optra N 4040 Service Manual

4040

Fuser (Abnormal Temperature) Service Check (923)

FRU
1 Thermistor
2 Fuser
3 System
Board
2-22
Action
The thermistor could be shorted. Turn the
power off and remove the fuser assembly.
Measure the resistance between the fuser
connector J50B-2 (FSRTH) and J50B-3
(GNDTH). The connector J50B is the lower
terminal of the left connector. If the resistance
is 1k Ohm or less, check the wiring from con-
nector J222-5 and J222-6 on the system
board to the thermistor. If it is normal, replace
the thermistor (18-23).
The fuser drive circuit in the power supply is
defective. Replace the power supply (5-10).
The system board could be defective (4-9).