WM2150HS - LG Washing Machine Service Manual (repair manual). Page 20

7. TEST MODE

7-1. SAFETY CAUTION

There's built-in AC 120V and DC power in output terminal of PWB assembly in common. Be careful electric
shock when disconnecting parts while trouble shooting. (Wear Electro Static Discharge gloves when working.)
After cutting off the power when changing PWB assembly, disconnect or assemble.
Be careful static when handling PWB assembly, and use Electro Static Discharge plastic pack when delivering
or keeping it. 

7-2. LOAD TEST MODE

The washer must be empty and the controls must be in the off state. 
1. Press the WASH/RINSE and SPIN SPEED buttons simultaneously.
2. Press the Power       button, while the above condition. Then buzzer will sound twice.
3. Press the Start/Pause      button repeatedly to cycle through the test modes.

7-3. HOW TO CHECK THE WATER LEVEL FREQUENCY

Press the CUSTOM and PRE-WASH buttons simultaneously.

None 

1 time 

2 times 

3 times 

4 times 

5 times 

6 times 

7 times 

8 times 

9 times 

10 times 

11 times 

Turns on all lamps and locks the door.

Tumble clockwise.

Low speed Spin.

High speed Spin.

Inlet valve for prewash turns on.

Inlet valve for main wash turns on.

Inlet valve for hot water turns on.

Inlet valve for bleach turns on.

Tumble counterclockwise.

Water Temperature (Thermistor)

Drain pump turns on.

Off

rpm (42~50)

rpm (55~65)

rpm (105~115)

Water level frequency (225~265)

Water level frequency (225~265)

Water level frequency (225~265)

Water level frequency (225~265)

rpm (42~50)

Water temperature [

°C

]

Water level frequency (225~265)

The digits indicate the water level frequency.

For example, if  the display indicate 41, 

the water level frequency is 20+(41X0.1) = 24.1 kHz.