7
4. Troubleshooting
Loud buzzing noise can be heard .
Oven can program
but timer does
not start
Open or loose wiring of secondary
interlock switch
Adjust door and interlock switches.
Off-alignment of primary interlock
Defective secondary interlock S/W
Turntable motor does
not rotate.
Open or loose wiring of
turntable motor.
Replace turntable motor.
Defective turntable motor
Oven stops operation
during cooking
Open or loose wiring of primary
interlock switch
Adjust door and latch switches.
Operation of thermal cutout
(Magnetron)
Sparks
Metallic ware or cooking dishes
touching on the oven wall
Inform the customer
: Do not use any type of
cookware with metallic trimming
Ceramic ware trimmed with gold or
silver powder also causes sparks
Loud buzzing noise
can be heard
Loose fan and fan motor
Tighten screws of fan motor.
Tighten screws of H.V.Transformer.
Replace H.V.Diode.
Loose screws on H.V.Transformer
Shorted H.V.Diode
Microwave
output is low
Decrease in power source voltage
Consult electrician.
Open or loose wiring of magnetron
filament circuit.
(Intermittent oscillation)
Aging of magnetron
Fan motor turns
on when plugged in
Loose wiring of door sensing switch
Consult electrician.
Oven does not
operate and return to
the plugged
in mode
Defective Ass’y PCB
Replace PCB main.
Noise from the
turntable motor when
it starts to operate.
Noise may result from the motor
Replace turntable motor.
Uneven cooking
Uneven intensity of microwave due
to its characteristics
Wrap thinner parts of the food with aluminum foil.
se plastic wrap or cover with a lid.
Stir once or twice while cooking foods such as
soup, cocoa, or milk.
Turntable motor does not rotate .
Oven can program
but timer does
not start
Open or loose wiring of secondary
interlock switch
Adjust door and interlock switches.
Off-alignment of primary interlock
Defective secondary interlock S/W
Turntable motor does
not rotate.
Open or loose wiring of
turntable motor.
Replace turntable motor.
Defective turntable motor
Oven stops operation
during cooking
Open or loose wiring of primary
interlock switch
Adjust door and latch switches.
Operation of thermal cutout
(Magnetron)
Sparks
Metallic ware or cooking dishes
touching on the oven wall
Inform the customer
: Do not use any type of
cookware with metallic trimming
Ceramic ware trimmed with gold or
silver powder also causes sparks
Loud buzzing noise
can be heard
Loose fan and fan motor
Tighten screws of fan motor.
Tighten screws of H.V.Transformer.
Replace H.V.Diode.
Loose screws on H.V.Transformer
Shorted H.V.Diode
Microwave
output is low
Decrease in power source voltage
Consult electrician.
Open or loose wiring of magnetron
filament circuit.
(Intermittent oscillation)
Aging of magnetron
Fan motor turns
on when plugged in
Loose wiring of door sensing switch
Consult electrician.
Oven does not
operate and return to
the plugged
in mode
Defective Ass’y PCB
Replace PCB main.
Noise from the
turntable motor when
it starts to operate.
Noise may result from the motor
Replace turntable motor.
Uneven cooking
Uneven intensity of microwave due
to its characteristics
Wrap thinner parts of the food with aluminum foil.
se plastic wrap or cover with a lid.
Stir once or twice while cooking foods such as
soup, cocoa, or milk.
Oven stops operation during cooking .
Oven can program
but timer does
not start
Open or loose wiring of secondary
interlock switch
Adjust door and interlock switches.
Off-alignment of primary interlock
Defective secondary interlock S/W
Turntable motor does
not rotate.
Open or loose wiring of
turntable motor.
Replace turntable motor.
Defective turntable motor
Oven stops operation
during cooking
Open or loose wiring of primary
interlock switch
Adjust door and latch switches.
Operation of thermal cutout
(Magnetron)
Sparks
Metallic ware or cooking dishes
touching on the oven wall
Inform the customer
: Do not use any type of
cookware with metallic trimming
Ceramic ware trimmed with gold or
silver powder also causes sparks
Loud buzzing noise
can be heard
Loose fan and fan motor
Tighten screws of fan motor.
Tighten screws of H.V.Transformer.
Replace H.V.Diode.
Loose screws on H.V.Transformer
Shorted H.V.Diode
Microwave
output is low
Decrease in power source voltage
Consult electrician.
Open or loose wiring of magnetron
filament circuit.
(Intermittent oscillation)
Aging of magnetron
Fan motor turns
on when plugged in
Loose wiring of door sensing switch
Consult electrician.
Oven does not
operate and return to
the plugged
in mode
Defective Ass’y PCB
Replace PCB main.
Noise from the
turntable motor when
it starts to operate.
Noise may result from the motor
Replace turntable motor.
Uneven cooking
Uneven intensity of microwave due
to its characteristics
Wrap thinner parts of the food with aluminum foil.
se plastic wrap or cover with a lid.
Stir once or twice while cooking foods such as
soup, cocoa, or milk.
Sparks .
Oven can program
but timer does
not start
Open or loose wiring of secondary
interlock switch
Adjust door and interlock switches.
Off-alignment of primary interlock
Defective secondary interlock S/W
Turntable motor does
not rotate.
Open or loose wiring of
turntable motor.
Replace turntable motor.
Defective turntable motor
Oven stops operation
during cooking
Open or loose wiring of primary
interlock switch
Adjust door and latch switches.
Operation of thermal cutout
(Magnetron)
Sparks
Metallic ware or cooking dishes
touching on the oven wall
Inform the customer
: Do not use any type of
cookware with metallic trimming
Ceramic ware trimmed with gold or
silver powder also causes sparks
Loud buzzing noise
can be heard
Loose fan and fan motor
Tighten screws of fan motor.
Tighten screws of H.V.Transformer.
Replace H.V.Diode.
Loose screws on H.V.Transformer
Shorted H.V.Diode
Microwave
output is low
Decrease in power source voltage
Consult electrician.
Open or loose wiring of magnetron
filament circuit.
(Intermittent oscillation)
Aging of magnetron
Fan motor turns
on when plugged in
Loose wiring of door sensing switch
Consult electrician.
Oven does not
operate and return to
the plugged
in mode
Defective Ass’y PCB
Replace PCB main.
Noise from the
turntable motor when
it starts to operate.
Noise may result from the motor
Replace turntable motor.
Uneven cooking
Uneven intensity of microwave due
to its characteristics
Wrap thinner parts of the food with aluminum foil.
se plastic wrap or cover with a lid.
Stir once or twice while cooking foods such as
soup, cocoa, or milk.
Uneven cooking .
Oven can program
but timer does
not start
Open or loose wiring of secondary
interlock switch
Adjust door and interlock switches.
Off-alignment of primary interlock
Defective secondary interlock S/W
Turntable motor does
not rotate.
Open or loose wiring of
turntable motor.
Replace turntable motor.
Defective turntable motor
Oven stops operation
during cooking
Open or loose wiring of primary
interlock switch
Adjust door and latch switches.
Operation of thermal cutout
(Magnetron)
Sparks
Metallic ware or cooking dishes
touching on the oven wall
Inform the customer
: Do not use any type of
cookware with metallic trimming
Ceramic ware trimmed with gold or
silver powder also causes sparks
Loud buzzing noise
can be heard
Loose fan and fan motor
Tighten screws of fan motor.
Tighten screws of H.V.Transformer.
Replace H.V.Diode.
Loose screws on H.V.Transformer
Shorted H.V.Diode
Microwave
output is low
Decrease in power source voltage
Consult electrician.
Open or loose wiring of magnetron
filament circuit.
(Intermittent oscillation)
Aging of magnetron
Fan motor turns
on when plugged in
Loose wiring of door sensing switch
Consult electrician.
Oven does not
operate and return to
the plugged
in mode
Defective Ass’y PCB
Replace PCB main.
Noise from the
turntable motor when
it starts to operate.
Noise may result from the motor
Replace turntable motor.
Uneven cooking
Uneven intensity of microwave due
to its characteristics
Wrap thinner parts of the food with aluminum foil.
se plastic wrap or cover with a lid.
Stir once or twice while cooking foods such as
soup, cocoa, or milk.
Noise from the turntable motor when it starts to operate .
Oven can program
but timer does
not start
Open or loose wiring of secondary
interlock switch
Adjust door and interlock switches.
Off-alignment of primary interlock
Defective secondary interlock S/W
Turntable motor does
not rotate.
Open or loose wiring of
turntable motor.
Replace turntable motor.
Defective turntable motor
Oven stops operation
during cooking
Open or loose wiring of primary
interlock switch
Adjust door and latch switches.
Operation of thermal cutout
(Magnetron)
Sparks
Metallic ware or cooking dishes
touching on the oven wall
Inform the customer
: Do not use any type of
cookware with metallic trimming
Ceramic ware trimmed with gold or
silver powder also causes sparks
Loud buzzing noise
can be heard
Loose fan and fan motor
Tighten screws of fan motor.
Tighten screws of H.V.Transformer.
Replace H.V.Diode.
Loose screws on H.V.Transformer
Shorted H.V.Diode
Microwave
output is low
Decrease in power source voltage
Consult electrician.
Open or loose wiring of magnetron
filament circuit.
(Intermittent oscillation)
Aging of magnetron
Fan motor turns
on when plugged in
Loose wiring of door sensing switch
Consult electrician.
Oven does not
operate and return to
the plugged
in mode
Defective Ass’y PCB
Replace PCB main.
Noise from the
turntable motor when
it starts to operate.
Noise may result from the motor
Replace turntable motor.
Uneven cooking
Uneven intensity of microwave due
to its characteristics
Wrap thinner parts of the food with aluminum foil.
se plastic wrap or cover with a lid.
Stir once or twice while cooking foods such as
soup, cocoa, or milk.
Summary of Contents for SMH7185STG
Page 3: ... 1 Precaution ...
