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9-2. DOOR LOCK SWITCH ASSEMBLY

AC
Common
terminal
of Valve

The Door Lock Switch Assembly consists of a Heating PTC, a Bimetal,
a Protection PTC, and a Solenoid. It locks the door during a wash cycle.

1. Operation for door closing

- After the system turns on, PTC heating starts up through terminal 2~4’s

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.

Test Points

(2) to (4)

(3) to (4)

(4) to (5)

(2) to (4)

Result

700-1500 

Ω

60-90 

Ω

Infinity

120 Vac

Remarks

At 77

°F 

(25

°C

)

At 77

°F 

(25

°C

)

Voltage Input

(2)

(3)

(4)

(5)

9-3. STATOR ASSEMBLY

The DD motor can be driven from stopped to maximum speed in infinite steps in
either direction.
There are 36 poles on the stator; 12 permanent magnets spaced around the rotor.
There are no brushes to wear out. Unlike a more traditional brushless motor, the
rotor surrounds the stator rather than being attached to it.

Test Points

Result

(1) to (2)

(2) to (3)

(3) to (1)

5-15 

Ω

5-15 

Ω

5-15 

Ω

The hall sensor determines the speed and direction of the motor.
It also can read that the load is off balance when the drum speed fluctuates.

If measuring voltage from the Main PCB Assembly to the Hall Sensor, use the
following steps:
1. Unplug power cord.
2. Remove rear washer panel.
3. Locate Hall sensor connector on the stator behind the rotor.
4. Place meter leads on terminals 5 to 4, white to gray.
5. Plug in power cord, close door, and press power button.

DO NOT PRESS START!

6. You should measure 10 to 15 Vdc. If 10 to 15 Vdc is present, control board,

white wire, and gray wire are OK! If not follow testing output voltages on control
board in next section.