Brother HL-2250DN Service Manual page 147

■ Operational check of electromagnetic clutch
When detect that the state of registration front sensor is changed, the regist
electromagnetic clutch is 200msON. When detect that the state of new toner sensor is
changed, the pickup electromagnetic clutch is 200msON.
CAUTION :
• When the operational check of electromagnetic clutch, the sounds is very low.
■ Operational check of motor
In the operational check of sensors, when the front cover is opened, close and open
and close the fuser cover while pressing the [Go] button. Release the [Go] button, and
close the front cover. and then the scanner motor is driven. The main motor is driven
after two seconds from the scanner motor driving. When the open the front cover, the
driving of the main motor and the scanner motor is stopped.
11) Continuous Grid Pattern Print Mode
This mode is to continuously print a grid pattern. The number of grid pattern prints is
displayed at the same time. The printer does not go back to the ready state unless the
power is turned off and on.
12) Fuser Unit Test Print
This is to print the following three patterns to check the fuser unit.
• Grid pattern
• Gray pattern
• Black pattern
When this operation is completed, the printer automatically return to the ready state.
13) EEPROM Value Dump Mode
This is to collectively print the present state of the EEPROM of all printers. When this
operation is completed, the printer automatically return to the ready state.
14) RAM Check
This is to execute a stricter RAM check than a standard one. If the result turns out
unaccepted, it considers an error, and all the LEDs blink. If it turns out accepted, the
Ready LED blink once, and then Error LED blink eight times. The printer does not return
to the ready state unless the power is turned off and on.
15) Printer Quality Test Pattern Print
This is to print four patterns to check the printer quality. The fourth pattern is continuous
printing, and continue the printing until unlock the function by keeping the [Go] button
pressed down.
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