HP LaserJet II Serie Manual De Instrucciones página 212

HP 33440/HP 33449 COMBINED SERVICE MANUAL
"41 ERROR" Message
Two displays,
41
ERROR and 51 ERROR, i ndicate a laser beam detect problem. The 41 ERROR is
displayed when the beam is "lost" for less than 2 seconds. An error condition of greater than 2
seconds will result in a 51 ERROR message. See the "51 ERROR Message" section for a discussion of
the 41 ERROR message condition.
"50 SERVICE" Fuser Malfunction
The purpose of the fusing system is to maintin a constant temperature on the Fusing Roller so
that the toner image is permanently fused to the paper. A high intensity fusing lamp, located in
the center of the Fusing Roller, provides the high temperature required for the fusing process.
While the printer is in standby mode, a temperature of 165° C is maintained on the Fusing RoUer.
While the printer is in printing mode, a temperature of 180° C is maintained.
The main components of the fusing system are the fusing lamp and its associated fusing and
pressure rollers, a Thermistor, Thermoprotector, and the AC controller/safety circuitry in the AC
Power Module. AC voltige is applied to the fuser bulb via the AC Power Module circuitry which
is regulated by the FUSER DR~ (FSRD) signal from the DC Controller PCA. Feedback to
the DC Controller is provided by the Thermistor signal (FSRTH ). The thermoprotection switch
is designed for over temperature protection and opens when the temperature reaches 210° C.
Overcurrent protection for the fising system is provided by circuit breaker CB101 on the AC
Power Module (see Figure 7-20).
For troubleshooting the printer when resting on its side, microswitch SW205 on the DC Controller
PCA provides additiond fusing system protection When the bottom cover of the printer is
removed, the microswitch closes and a resistor is placed in parallel to the Thermistor circuitry.
This resistice simulates the Fusing Roller at temperature and this prevents the fusing lamp from
operating under this condition.
The following conditions result in a fusing erroc
1. A temperature below 140° C.
2.
A temperature above 230° C.
3. A condition wherein
a
temperature of 165° C is NOT reached within 90 seconds ~er power-up.
If any of the
fusing error conditions occur, the DC
Controller posts a 50 SERVICEerror. The error
cannot be cleared until the printer has been powered down for a ten-minute interval.
Note
E the printer displays 50 SERVICEerror, allow a ten-minute power down interval
Pt
to elapse for the error to clear.
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