Service Manual

TESTING – DRYER
27” Stacked Laundry Center
n
4-9
For Service Technician Use Only
TEST #2: Motor Circuit
This test will check the wiring to the motor and the motor
itself.
1. Unplug dryer or disconnect power.
2. Check for loose, worn, or damaged drum belt—repair as
necessary.
3. Door Switch problems can be uncovered by following
procedure under TEST #5: Door Switch, page 4-14.
4. Check the wiring and components in the motor circuit by
referring to the appropriate wiring diagram on pages 4-4
to 4-7 or the Motor Strip Circuit below (see Figure 1).
Check the thermal fuse. See TEST #3a: Thermal Fuse, page
4-11.
Connue with step 5 to test the remaining components in
the motor circuit.
5. Check the drive motor and belt switch. Slowly remove the
drum belt.
6. Remove the white connector from the drive motor switch.
7. Remove the bare copper wire terminal from pin 5 of black
drive motor switch.
8. Using the appropriate wiring diagram on pages 4-4 to 4-7,
check for the resistance values of the motor’s Main and
Start winding coils as shown in the following table.
NOTE: Main and Start winding coils must be checked at
the motor.
Winding
Resistance
in ohms
Contact Points of Measurements
MAIN 2.4 - 3.6
Lt Blue wire in back at pin 4
and bare copper wire terminal
removed from pin 5 of black drive
motor switch
START 2.4 - 3.8
Lt Blue wire in back at pin 4 and
bare copper wire terminal on pin
3 of black drive motor switch
¾ If the resistance at the motor is correct, there is an
open circuit between the motor and the mer. Check
for a belt switch problem (see step 9) and check and
repair the main wiring harness.
¾ If the Main or Start winding resistance is much greater
or less than the values listed in the table above, replace
the motor.
9. Check the belt switch by measuring resistance between
the two light blue wires in the belt switch connector block
while pushing up the belt switch pulley.
¾ If the resistance reading goes from open to a few ohms
as pulley arm closes the switch, belt switch is good. If
not, replace the belt switch.
¾ If belt switch is good and there is sll an open circuit,
check and repair the main wiring harness.
10. Reassemble all parts and panels.
11. Plug in dryer or reconnect power.
Pluggable Drive Motor Switch
WARNING
Electrical Shock Hazard
Disconnect power before servicing.
Failure to do so can result in death or
electrical shock.
Replace all parts and panels before operating.
C
L1
MOTOR STRIP CIRCUIT
BK
W
LBU
DRIVE MOTOR
N
MAIN
START
DOOR SWITCH
3M
THERMAL
FUSE
5M
6M
2M
1M
LBU
BK
W
LBU
CENTRIFUGAL SWITCH
2.4-3.8 Ω
2.4-3.6 Ω
4M
B
TIMER
BELT
SWITCH
W
START
NO COM
Figure 1 - Motor Strip Circuit
MOTOR CIRCUIT
Black
Figure 2