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1. Be careful of electric shock if disconnecting parts while troubleshooting.
2. First of all, check the connection of each electrical terminal with the wiring diagram.
3. If you replace the MAIN PCB ASSEMBLY, reinsert the connectors correctly.A

Replace the
DISPLAY PCB
ASSEMBLY

Is three pin wire of display
PCB broken?

Replace the 
MAIN PCB
ASSEMBLY

Is LED on while the power is
on?

Check the fuse or
reset the circuit
breaker

Is the supplied voltage
120V AC?(+10%, -15%)

Reconnect or
repair the
connector

Is the connector connected 
to PCB/Noise filter
disconnected or
disassembled?

Alternate with
explanation

Is the current rating of multi-
outlet power strip enough?
(Avoid connecting several
electric devices )

Replace the
DISPLAY PCB
ASSEMBLY

Is the display PCB broken?
(check the buzzer sound 
and LED light while push the
button )

Is the connector connected to
Main PCB / Display PCB
disconnected or
disassembled?

Reconnect or
Repair the
connector

Is the button of panel stuck?

Repair the button

When Resistance (Ohm) checking the Component, be sure to turn the power off, and do
voltage discharge sufficiently.

MAIN PCB 
ASSEMBLY 

3 3 

1 1 

RD1 

WH1 

Vac 

1 1 

2 2 

2 2 

Test Points

WH (1) to RD (1)

WH (3) to RD (2)

Result

0 

Ω

0 

Ω

(1)

(3)

(1)

(2)

The Door Lock Switch Assembly consists of a DC Motor, a Bimetal, a Protection PTC, Sensing Point.
It locks the door during a wash cycle.

- After the system turns on, Micom sending motor locking signal.
- 12V motor is working.
- Spring that connected with motor shaft is working.
- The hook that connected with spring is pushed out.
- Door lock is detected when switch sensing point is detected lock position.
- The motor stop.

➾ Door locked 

The maximum, allowable number of impulse authorizations is 3

➾ Upon the third authorization of the impulse,

the position of hook 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.

- With a temporary stop, door automatically opens by hook moving after micom send open signal

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.