Canon LBP-1210 Service Manual page 102

CHAPTER 2
6. Fan motor control circuit
This circuit controls the fan motor on the instruction from the CPU.
The circuit is illustrated below.
Engine Controller PCB
CPU
IC201
23
P04
24
P05
The fan motor is a DC brushless motor with a built-in Hall device. This motor is unified with
the motor drive circuit.
To rotate the fan motor, the CPU turns ON the pick-up solenoid and simultaneously sets the
No.23 pin "H". When the main motor stops at print completion, the CPU rotates the fan motor
for about 30 seconds and then sets the pin "L" to stop the fan motor.
The CPU determines a fan motor failure and notifies it to the interface controller under the
following conditions:
1) The FAN LOCK DETECTION (FLOCK) signal is not set "L" within about 10 seconds after the
start of fan motor rotation.
2) The FAN LOCK DETECTION (FLOCK) signal is set "H" continuously for 10 seconds during
fan motor rotation.
2 - 16
Fan motor drive circuit
+24V
+3.3V
Figure 2-2-6
Air intake fan
FM1
J203-1
FANON
J203-2
J203-3
FLOCK