LG WT4870CW Service Manual ▷ View online
33
LOCKED MOTOR ERROR
Yes
Is LE displayed?
Reconnect
the connector
(connector /
wire / motor )
Check the connectors below.
Is the connector disconnected
or disassembled?
(motor hall sensor connector,
motor drive connector)
- Part of main PCB
assembly (YL3, BL6)
Motor Drive
Hall Sensor
- Part of wire
Yes
No
No
Is rotor magnet cracked?
Is hall sensor out of order ?
Yes
Yes
Check the IPM in the
controller. Is IPM short?
Yes
No
Yes
Is the resistance values
in the range of 5 to15 Ω?
(U-V, V-W, W-V
:U=1, V=2, W=3)
- After pull out the YL3
connector, check the terminal
of the connector in wire.
No
Replace the
ROTOR
Replace the
STATOR
Replace the Hall
sensor
Replace the
MAIN PCB
ASSEMBLY
- Part of motor
Motor
Hall Sensor
Hall Sensor
Hall Sensor
Hall Sensor
Hall Sensor
Hall Sensor
Hall Sensor
Hall Sensor
Hall Sensor
Hall Sensor
Hall Sensor
Hall Sensor
Hall Sensor
Hall Sensor
Motor Drive
Motor Drive
Motor Drive
Motor Drive
Motor Drive
Motor Drive
Motor Drive
Motor Drive
Motor Drive
Motor Drive
Motor Drive
Motor Drive
Motor Drive
Motor Drive
Magnet
34
UNBALANCE ERROR
Yes
Is UE displayed?
Put laundry evenly
In the DRUM
assembly
No
Does the laundry lean toward
one side, not evenly put in the
DRUM assembly?
Is the washing machine
installed at an angle?
Yes
Yes
Does the inlet valve work
when the power is not
applied?
Replace the INLET VALVE
ASSEMBLY
No
Adjust the height of
washing machine
to be kept
horizontally
Yes
If the inlet valve
works
continuously when
the power is
applied, replace
the MAIN PCB
ASSEMBLY
OVER FLOW ERROR
Yes
Is FE displayed?
Check the AIR
CHAMBER and the
tube (clogged).
Yes
When you enter the service
mode, is the water level
frequency over 21.0 kHz?
No
PRESSURE SENSOR ERROR
35
Yes
Is PE displayed?
Reconnect or
repair the
connector
No
Is the connector connected to
pressure sensor disconnected
or disassembled?
Yes
Replace the
pressure switch
No
Is the resistance of the
pressure sensor out of range?
(pin 1~ pin 3)
(21~23 Ω±10%)
Yes
No
Is the AIR CHAMBER and the
tube clogged?
Yes
Fix the air
chamber and
remove the foreign
material
Replace the MAIN PCB
assembly
4-7. OTHER TROUBLESHOOTING
36
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.
NO POWER
Replace the
DISPLAY PCB
ASSEMBLY
Is three pin wire of display
PCB broken?
Yes
Replace the MAIN
PCB ASSEMBLY
No
Is LED on while the power is
on?
Yes
Check the fuse or
reset the circuit
breaker
Yes
Is the supplied voltage
120V AC?(+10%, -15%)
No
Reconnect or
repair the
connector
Yes
Is the connector connected to
PCB/Noise filter disconnected
or disassembled?
No
Alternate with
explanation
Yes
Is the current rating of multi-
outlet power strip enough?
(Avoid connecting several
electric devices)
No
Display PCB
Connecting connector
MAIN PCB~ Display PCB
CAUTION
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