LG GR-J303TG, Service Manual

Page: 19 / 46

3-2-7. TEMPERATURE SENSING CIRCUIT
1.Temperature adjustment at the lower compartment consists of the circuit part for driving the damper, as electronic single
motor damper, to open or close the baffle and the reed switch part to detect open/close status of the damper.
2. Drives the motor, and if there is no status change of the reed switch within 2 minutes, determines it as failure and displays
as failure (See 3-1-11. Failure Diagnosis Function).
3. Rotates once for 15 seconds irrespective of temperature to detect damper status in input of initial power (initial drive
inspection).
4. Open/Close of the damper, status of the reed switch and No.1 pin input of the IC1 (MICOM) are as follows:
<SINGLE MOTOR DAMPER>
u The above time is time until the single motor stops after status change of the reed switch.
- 19 -
Single Motor Damper
100V~127V
deleted
Open/Close status
of lower damper
Single Damper
Reed Switch
IC1 (MICOM) “H” : 5V
No.1 pin input “L” : 0V
2sec
Operation Stop
Operation Stop
OPEN
CLOSE
ON
OFF
Position Lower Damper status
Open
Close