LG WM3988HMA / WM3988HWA Service Manual ▷ View online
24
8-4. TROUBLESHOOTING WITH ERROR
INLET VALVE ERROR
Is displayed?
When you press both
WASH/RINSE button and
SOIL LEVEL button
simultaneously,
is the water level frequency
below 24.6 kHz?
WASH/RINSE button and
SOIL LEVEL button
simultaneously,
is the water level frequency
below 24.6 kHz?
(Refer to 7-4.)
Is filter inlet valve clogged
with foreign material?
with foreign material?
Is the connector connected to
inlet valve assembly
disconnected or
disassembled?
inlet valve assembly
disconnected or
disassembled?
Is resistance between
each terminal of INLET
VALVE ASSEMBLY
0.8-1.2 k
each terminal of INLET
VALVE ASSEMBLY
0.8-1.2 k
Ω?
(Refer to 9-5 inlet valve
assembly)
assembly)
Clean or
replace the filter.
replace the filter.
Check the AIR
CHAMBER
and the tube
(clogged).
CHAMBER
and the tube
(clogged).
Yes
No
No
Yes
Yes
Reconnect or
repair
the connector.
repair
the connector.
Replace the
INLET VALVE
ASSEMBLY.
INLET VALVE
ASSEMBLY.
Yes
Yes
Is the voltage of the inlet
valve connector 120 V AC?
(Check the all terminal of
INLET VALVE ASSEMBLY
while the power is on.)
valve connector 120 V AC?
(Check the all terminal of
INLET VALVE ASSEMBLY
while the power is on.)
Replace the
INLET VALVE
ASSEMBLY.
INLET VALVE
ASSEMBLY.
No
Yes
Is the connector connected to
MAIN PWB assembly
disconnected or dis-
assembled?(NA4, BL3, WH)
MAIN PWB assembly
disconnected or dis-
assembled?(NA4, BL3, WH)
Reconnect or
repair
the connector.
repair
the connector.
No
Yes
Yes
Is Electrical connection
correct?
correct?
(Refer to 9-5 wiring diagram)
Replace the
MAIN HARNESS.
MAIN HARNESS.
No
No
After checking connector,
is the water level frequency
below 24.6 kHz?
is the water level frequency
below 24.6 kHz?
(Refer to 7-4)
Replace the MAIN PWB
ASSEMBLY.
ASSEMBLY.
[Note] Environmental safety check list
1) No water tap leakage
2) No water tap freeze
3) No entanglement of water supply hose
4) No water shortage
5) No shrinkage on water supply hose due to
1) No water tap leakage
2) No water tap freeze
3) No entanglement of water supply hose
4) No water shortage
5) No shrinkage on water supply hose due to
a possible misuse of hot and cold water
6) No water supply hose leakage
Check the
PRESSURE
SWITCH.
PRESSURE
SWITCH.
Yes
No
No
25
DRAIN ERROR
Is displayed?
Is the connector connected
to pump motor assembly
disconnected or
disassembled?
to pump motor assembly
disconnected or
disassembled?
Reconnect or
repair
the connector.
repair
the connector.
Yes
Circulation pump
Yes
Drain pump
Connection connector
No
Yes
When you press both
WASH/RINSE button and
SOIL LEVEL button
simultaneously, is the
water level frequency
below 26.0 kHz?
WASH/RINSE button and
SOIL LEVEL button
simultaneously, is the
water level frequency
below 26.0 kHz?
(Refer to 7-4)
Check the AIR
CHAMBER,
the tube
(clogged),
and press
switch
CHAMBER,
the tube
(clogged),
and press
switch
Is the coil of the drain
pump too high or low?
(resistance of the coil
is 10-20
pump too high or low?
(resistance of the coil
is 10-20
Ω)
(Refer to 9-4 Pump motor
assembly)
assembly)
Replace the
DRAIN
PUMP
ASSEMBLY.
DRAIN
PUMP
ASSEMBLY.
No
Yes
Is the voltage between
connectors out of range?
(WH pin1~ BL3 pin1)
- After remove Terminal
Position Assurance (TPA)
of connector, check as
follows.
connectors out of range?
(WH pin1~ BL3 pin1)
- After remove Terminal
Position Assurance (TPA)
of connector, check as
follows.
- Pump running : 120V±5%
- Stopped Motor/Pump : 0~1V Method
1. Press the Power button, while the SPIN SPEED
- Stopped Motor/Pump : 0~1V Method
1. Press the Power button, while the SPIN SPEED
button and SOIL LEVEL button is pressed
simultaneously.
simultaneously.
2. Press Start/Pause button.
: 1 time
Pump slow-speed running
: 2 times
Pump mid-speed running
: 3 times
Pump high-speed running
: 4 times
Stop the Motor/Pump
[Note] Environmental check list
1) The drainage hose must not stay in a lower position.
2) The drainage hose must not be bent or
1) The drainage hose must not stay in a lower position.
2) The drainage hose must not be bent or
clogged in any way due to the surrounding
physical configuration.
physical configuration.
3) The drainage hose must not get frozen at all times.
4) The drainage pump must not have any improper
4) The drainage pump must not have any improper
substance or material inside that may cause
a machine breakdown.
a machine breakdown.
Replace the
MAIN PWB
ASSEMBLY.
MAIN PWB
ASSEMBLY.
Yes
No
26
HEATING ERROR
Is displayed?
Is the connector connected
to heater disconnected or
disassembled?
to heater disconnected or
disassembled?
Reconnect or
repair
the connector
repair
the connector
Yes
Yes
Is Check heater
resistance out of range?
(12~18
resistance out of range?
(12~18
Ω)
(Refer to 9-6 Heater
assembly.)
assembly.)
Replace the
HEATER
ASSEMBLY
HEATER
ASSEMBLY
Yes
No
No
Is thermistor resistance
out of range?
(about 39.5 k
out of range?
(about 39.5 k
Ω at 30
°C
)
(Refer to 9-7 thermistor
assembly)
assembly)
Replace the
THERMISTOR
ASSEMBLY
THERMISTOR
ASSEMBLY
Yes
No
Check the trans of water
infiltration into thermistor
terminal.
- Does the water infiltrate
infiltration into thermistor
terminal.
- Does the water infiltrate
thermistor terminal?
[Note]
Chances that the cause occurs from the
main controller are very little.
Sensing part of the circuit (tE) consists of
only resistors and capacitors.
Chances that the cause occurs from the
main controller are very little.
Sensing part of the circuit (tE) consists of
only resistors and capacitors.
Replace the
THERMISTOR
ASSEMBLY
THERMISTOR
ASSEMBLY
Yes
Steam generator heater
Wash heater
Is the connector connected to
thermistor disconnected or
disassembled?
thermistor disconnected or
disassembled?
Reconnect or
repair
the connector
repair
the connector
Yes
No
Steam generator thermistor
Wash thermistor
Dry thermistor
Dry thermistor
27
LOCKED MOTOR ERROR
Is displayed?
Check the connectors below.
Is the connector disconnected
or disassembled?
(motor hall sensor connector,
motor drive connector)
- part of main PWB
Is the connector disconnected
or disassembled?
(motor hall sensor connector,
motor drive connector)
- part of main PWB
assembly (NA1, RD4)
Reconnect
the connector.
(connector /
wire / motor)
the connector.
(connector /
wire / motor)
Replace
the ROTOR
the ROTOR
Yes
Yes
Motor Drive
Is rotor magnet cracked?
Hall sensor
Motor Drive Hall Sensor
- part of wire
- part of motor
Motor
Yes
No
Yes
Yes
Magnet
Replace
the STATOR
the STATOR
Is the resistance values
in the range of 5 to 15
in the range of 5 to 15
Ω?
(U-V, V-W, W-V
:U=1, V=2, W=3)
- After pull out the RD4
:U=1, V=2, W=3)
- After pull out the RD4
connector, check the
terminal of the connector
in wire. (Red 3P, male)
terminal of the connector
in wire. (Red 3P, male)
No
Replace
the Hall
sensor
the Hall
sensor
Is hall sensor out of
order?
order?
(Refer to 9-3
Stator assembly/Hall
sensor.)
sensor.)
Yes
No
Replace the
MAIN PWB
ASSEMBLY
MAIN PWB
ASSEMBLY
Check the IPM in the
controller.
controller.
No
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