4.4.11.5. Toner Empty Sensor Circuit

Toner empty sensor detects the shortage of toner. IC004 ( CPU ) sends the nTECTL ( pin7, IC004 ) signal to Q009. When the
nTECTL is low level, transistors Q009 and Q003 are turned on. and LED D517 emits light. If the toner is shorted ( empty ),the light
from LED D517 passes through the lens of the Toner Cartridge. When the photo transistor PI451 receives the light, the PI451 is
turned on, and the TESEN ( pin4, IC004 ) signal becomes low.

4.4.12. Fan Control Circuit

FANCTL:
1. Full Power Mode
When FANCTL signal ( pin 6, IC004 ) is high, pin 7 of IC002 goes high, transistors Q018 and Q020 are turned on. This supplies
+24V Power to Fan motor and rotates the Fan.
2. Reducing Power Mode ( Quiet Mode )
Pulse signal ( see below ) is output from pin 6 of IC004.
This pulse signal is integrated by R137 and C108. Voltage of ( A ) is stabilized at approx. 2V. Pin 6 of IC002 is 0V.
When the voltage of ( B ) is lower than the voltage of ( A ), pin 7 of IC002 goes high, Q018 and Q020 are turned on, then the
voltage of ( B ) increases. When the voltage of ( B ) is higher than ( A ), pin 7 of IC002 goes low, Q018 and Q020 areturned
off, then voltage of ( B ) decreases. Thus the voltage of ( B ) is controlled almost same as the voltage of ( A ) ( = approx. 2V
). Since the resistor network of R141 and R142 divide the voltage of ( C ) into 1/8, the voltageof ( C ) is controlled approx. 16V
( = 2V x 8 ).
FAN Control Mode
Mode FAN Power
Warm Up Full
Printing Full
Others Reduced
FANERR:
This signal is used for detecting whether the rotation of fan motor is proper or not. When the fan motor is not rotating properly or
is locked, this signal becomes a high and inputted into pin18 of IC004.
71
KX-P7105 / KX-P7110