Kenmore 796.4107 31 Series, Service Manual

Page: 38 / 59

39
9-2. DOOR LOCK SWITCH ASSEMBLY
Wiring
diagram
Circuit in the MAIN PWB / Wiring Diagram
MAIN PWB
Vdc
Vac
MICOM
12V
4 1
3 2
4 1
3 2
Relay
Relay
NA4
1
2
3
4 1
2
3
4 2
3
4
PTC
PTC
Door switch
SOLENOID
5
YL
BL
RD
BK
AC
Common
terminal
of valve
Function
The door lock switch assembly consists of a heating PTC, a bimetal,
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
4 authorizing the power on.
- After PTC heating starts up and before solenoid operation is driven,
force the system to the off position through CAM.
Door close
- Authorizing one impulse through terminal 3~4 (PTC & solenoid) will
make the door locked.
- Door lock is detected when switches in terminal 4~5 are set closed.
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.
- Authorizing the impulse occurs in 4.5 seconds upon input for max
performance and two authorization processes are allowed at most.
Normal operation period of PTC heating: 1.5 – 5 seconds.
(Defects from the development process.)
2. Operation for door opening
- With a temporary stop, door automatically opens by CAM rotations after
authorizing the impulse from the terminal, 3 ~ 4 and the power turns
off – maximum of 3 times of the authorizing period.
- Upon the fourth authorization of the impulse, the position of CAM goes
back to the door-close position.