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NOTE: This test has two parts. The best test of the door switch system is done in the diagnostic mode. This
FUNCTIONAL TEST will test the door switch, wiring harness and PCB operation. If the results of this test are
normal, the door switch system and PCB response are normal. The problem is somewhere else.
FUNCTIONAL TEST (Control)
1. Enter the diagnostic mode. (See DIAGNOSTIC TEST MODE.)
2. With the door closed, press the START/PAUSE button once. The dryer will start tumbling without heat.
3. Open the door. The drum will stop tumbling. The “dE” error code should be displayed, the chime should sound seven times (if turned on), and
the drum light (if equipped) should come on. If the “dE” error code is not displayed or the light does not come on, proceed with the
MECHANICAL TEST below. If the error displays and light comes on, the door switch is working properly.
Test 5
Door Switch Test
isY
X
Z
[
Y
~o[
X
Z
[
Y
NO
NO
NO
YES
YES
YES
WH4
Disconnect the WH1 and BL3 connector
from the main PCB.
Measure the resistance between the
NA6- (GN) pin and a chassis
ground screw.
Is the resistance <1 ?
Disconnect the BL2 and WH4 connector
from the main PCB.
Measure the resistance between
BL2- (WH) and WH4- (YL).
Is the resistance <1 with the
door closed and with the door
open?
*Skip this step if the dryer does not have
a drum light.
Disconnect the WH4 and the black tab
relay connectors from the main PCB.
Measure the resistance between
WH4- (YL) and WH4- (BK).
Is the resistance <1 with the door
opened and
with the door closed?
Refer to the individual door switch and light
bulb/socket component tests.
•
Replace the main
PCB.
•
Check all wiring
harness
connections wire
and ground
screws.
•
Replace the light
bulb.
•
Replace the light
socket.
FOR LG TECHNICIAN
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Test 6
Heater Switch Test - Electric Type
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
YL3
BK
YL3
WH
Caution
Trouble
Symptom
Measurement
Condition
Before measuring resistance, be sure to turn the power off, and do voltage discharge.
(When discharging, contact the metal plug of the power cord with a ground line.)
While operating, Heating will not work. Drying time takes longer.
After turning the power off, measure the resistance.
Enter diagnostic mode and press the
START/PAUSE button twice. Measure the
voltage between YL3- (WH) and the YL wire
on the black tab relay. Is the voltage 240 VAC?
Disconnect the YL3, black tab relay and white tab relay
connectors at the main PCB.
Measure the resistance between YL3- (WH) and the
BL wire on the black tab relay connector.
Is the resistance 18-22 ?
Measure the resistance between YL3-
(WH) and the YL wire on the white tab relay
connector. Is the resistance 18-22
?
?
Measure the resistance between the BL wire on the
black tab relay and the YL wire on the white tab
relay connectors. Is the resistance 36-44
Measure the resistance between terminals 1
(RD) and the heater housing.
Is the resistance <1 ?
Refer to the hi-limit thermostat and
thermal cut off component tests.
•
Check power supply.
•
Check wiring and
connectors to
the element.
•
See element
component test.
•
Check wiring and
connectors
to the element.
•
See element
component test.
•
Check wiring
and connectors to the
element.
•
See element
component test.
•
Replace the
element.
TH3
L2(Red) L2S(White)
TH2
L2S(White)
L2
(Red)
TH3
TH2
L2D(White)
Only for FLOW SENSE model
Others
Wires
L2(Red)
L2D(White) : Go to the duct(YL3 in main pcb)
L2S(White) : Go to the safety.
BK
WH
FOR LG TECHNICIAN
43
