The laser printer is a printout device that integrates laser scanning techniques, electronic technology, electrostatic imaging techniques. It has the characteristics of fast printing speed, good print quality, high resolution, low noise, is an important computer peripheral device. With the emergence of network printers, it is increasingly widely used in office automation, printing, publication, research and other industries.
Maintenance fault example
Fault 1: A laser printer image is obviously black, while white. In the replacement of the toner cartridge, the component is all cleaned or still exists.
Overhaul method: By maintaining the optical part of the laser printer, the fault is resolved, mainly to open the outer casing of the laser printer, open the black plastic box, use a clean lens paper to rub the plurality of back mirrors, and then put a few optical The lens is clean,
Restore the removal plastic box, pay attention to install the wiring card connector. After booting, the imprinted writing is very full.
Fault 2: One Canon
The ST laser printer often has a failure of the heating lamp. There is only one power light after power on, and the machine cannot work properly.
Overhaul method: By examination, it is not the problem of the fixer, nor is the problem of power, small relays, but a small box next to the power box.
102J small resistance and circuit board are not good, because it is two-sided circuit board,
Welding two sides, the troubleshooting after electrocromic iron is welded. This fault is
The ST laser printer is generally common, but sometimes the heating lamp is unity and the power control part is one-way thyristor failure. Fixed tubes, thermistors, and thermal protector are also more common. If the fixing lamp is burned, the thermistor is not good, the heat protector is open to replace.
Failure three: one Canon
The Heating lamp of the BXII laser printer is sometimes bright, sometimes it is not bright.
Maintenance method: When the heating lamp is not lit, use a multimeter to check
There is no connection between the two lamps, there is
7 thin wires are broken, because
BXI and
The KT laser printer fixing part and host connection are active, and several wires are often disassembled. If the heating lamp does not light, it can be used normally after a long time, which is a thermistor. Replace the new thermistor and the fault can be resolved. Measure the normal thermistor cold state with a multimeter
320kΩ, hot mode
1.45kΩ.
Fault 4: Output image color, not clear
One
CANON LBP type laser printer, output image is shallow, basically unclear. Try to adjust the contrast knob to the maximum file. The output sample is still unclear. Consider mirror dirt, wipe the mirror and focus lens with alcohol cotton balls, and the fault is still. Check if the transfer electrode is normal, no abnormalities, and clean the electric wire clean, and the fault has not been excluded. Check the powder box charging electrode wire, intact, check the high pressure and high pressure contacts,
Note The fault is not related to the electrode wire.
Further inspection, one spring sheet of the sensitive sensing switch of the laser drive circuit is found to cause the above fault to cause the printer to cause the above fault. After replacing the new spring sheet, troubleshooting.
Failed five: fixed heating is not normal
A Canon laser printer, the power indicator is on the power-on, ready
/ Waiting for the indicator light, the fixture is only flashed once again, and it is sometimes not working at all.
Based on the failure phenomenon, it is suspected that the fixing heater is adversely or damaged. Remove the fixing heater portion, detect the normal, detect the thermistor and temperature sensor and protection circuits with a multimeter-e-mesh power resistance gear, and have not found problems. Check that the main control board control interface circuit has not seen an exception.
Further inspection of the heating drive circuit and find that the controllable silicon has problems. After replacing new controllable silicon, the fixing heater will return to normal, troubleshooting
