Component Testing Procedures
!
WARNING
To avoid risk of electrical shock, personal injury or death, disconnect power to oven and discharge capacitor
before servicing, unless testing requires it.
16023053 Rev. 0
©2004 Maytag Appliances Company
16
Illustration Component
Test
Results
Thermal Cutout
Disconnect all wires from TCO.
Measure resistance across terminals.
Magnetron TCO ..........................................
Cavity TCO..................................................
Open at 293
°
F (145
°
C) and
closed at 185
°
F (85
°
C)
Opens at 194
°
F (90
°
C)
Capacitor
Discharge Capacitors
Remove wires from capacitor terminals and
connect ohmmeter, set on highest
resistance scale to terminals.
Also check between each terminal and
capacitor case.
Between Terminals: Meter should
momentarily deflect towards zero then
return to over 5 M
Ω
. IF no deflection
occurs, or if continuous deflection
occurs, replace capacitor.
Terminal to Case: Infinite resistance
Diode Assembly
Discharge Capacitors
Remove diode lead from capacitor and
connect ohmmeter.
Reverse leads for second test.
Infinite resistance should be measured
in one direction and 50K
Ω
or more in
the opposite direction.
NOTE:
Analog meter must contain a
battery of 6 volts minimum.
Magnetron
Discharge Capacitors
Remove wires from magnetron and connect
ohmmeter to terminals. Also check
between each terminal and ground.
Between Terminals: Less than 1
Ω
Each terminal to ground measures
Infinite resistance.
Note:
This test is not conclusive. If
oven does not heat and all other
components test good replace the
magnetron and re-test.
Fan Motor
Remove all wires from motor.
Measure resistance across coil ...................
Approximately 50 - 150
Ω
Stirrer motor
Remove all wires from motor.
Measure resistance across coil ...................
Approximately 2 – 4K
Ω
Red
White
Primary
Transformer
Discharge Capacitors
Remove all wires from terminals.
Measure resistance from:
Primary ....................................................
Filament (white leads)..............................
Secondary (red lead) to transformer base
plate.........................................................
<1
Ω
<1
Ω
Approximately 60 -90
Ω
Secondary
switch
Monitor
switch
Primary
switch
COM
NO
NO
COM
COM
NC
Interlock switches
Disconnect wires to switch
With door open measure resistance from:
COM to N.O.
⎯
Secondary .........................
COM to N.C.
⎯
Monitor ..............................
COM to N.O.
⎯
Primary..............................
With door closed measure resistance from:
COM to N.O.
⎯
Secondary .........................
COM to N.C.
⎯
Monitor ..............................
COM to N.O.
⎯
Primary..............................
Infinite
Ω
0
Ω
Infinite
Ω
0
Ω
Infinite
Ω
0
Ω
