LG WM3670H A Series Service Manual page 34

8-2. DOOR LOCK SWITCH ASSEMBLY
Wiring
Circuit in the MAIN PWB / Wiring Diagram
diagram
The door lock switch assembly consists of a heating PTC, a bimetal,
Function
a protection PTC, and a solenoid. It locks the door during the wash cycle.
1. Operation for door closing
- After the system turns on, PTC heating starts up through terminals 2 and
- After PTC heating starts up and before solenoid operation is driven,
- Authorizing one impulse through terminal 3~4 (PTC & solenoid) will
- Door lock is detected when switches in terminal 4~5 are set closed.
- Authorizing the impulse occurs in 4.5 seconds upon input for max
2. Operation for door opening
- With a temporary stop, door automatically opens by CAM rotations after
- Upon the fourth authorization of the impulse, the position of CAM goes
MICOM
12V
Relay
4 authorizing the power on.
force the system to the off position through CAM.
Door close
make the door locked.
CAM rotation will forcibly clear off the connection.
The maximum, allowable number of impulse authorizations is 2.
Upon the third authorization of the impulse, the position of CAM goes
back to the door-open position.
performance and two authorization processes are allowed at most.
Normal operation period of PTC heating: 1.5 – 5 seconds.
(Defects from the development process.)
authorizing the impulse from the terminal, 3 ~ 4 and the power turns
off – maximum of 3 times of the authorizing period.
back to the door-close position.
MAIN PWB
Vdc
YL
1 1 2
BL
2 2 3
RD
3 3 4
BK
4 4
5
NA4
AC
Relay
Common
terminal
of valve
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Vac
Door switch