6-1 Electrical Malfunction(continued)
SYMPTOM
CAUSE
CORRECTIONS
Oven lamp goes off
1. Loose lead wire or open lamp
filament
1. Misadjustment of latch switch
2. Defective primary latch switch
Tighten lamp lead wire or replace
with a new lamp
Microwave output is low;.
Oven takes longer time to
cook food.
(No heat while oven lamp
and ventilation)
1. Decrease in power source voltage.
2. Open or loose wiring of magnetron
filament circuit.(Intermittent oscillation)
3. Aging of magnetron
4. Defective high voltage components
H.V.Transformer
H.V. Capacitor
H.V.Diode, H.V.Fuse
Magnetron
Consult electrician.
Check high voltage component
according to component test
procedure and replace if defective.
Oven does not operate and
return to the plugged in mode.
Defective Ass’y PCB
Replace PCB main.
Loud buzzing noise can be
heard.
1. Loose fan and Fan motor
2. Loose screws on H.V.Transformer
3. Shorted H.V.Diode
4. Loose or missing screws on
Cover-Back.
Tighten screws of Fan motor.
Tighten screws of H.V.Transformer.
Replace H.V.Diode.
Tighten screws of Cover-Back
Drive motor not work.
(Ass’y stirrer does not
rotate.)
1. Open or loose wiring of turntable motor.
2. Defective turntable motor.
3. Defective ass’y stirrer
Check the wire of drive motor
Replace drive motor.
Replace ass’y stirrer
Oven stops operation during
cooking
1. Operation of thermal cutout
(Magnetron or Cavity)
2. Fan motor does not rotate.
Adjust door and latch switches.
Replace Fan motor.
Sparks
1. Metallic ware or cooking dishes
touching on the oven wall.
2. Ceramic ware trimmed with gold or
silver powder also causes sparks.
Inform the customer of proper use.
Do not use any type of cookware
with metallic trimming.
Uneven cooking
Uneven intensity of microwave due to its
characteristics.
Wrap thinner parts of the food with
aluminum foil.
Use 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.
Noise may result from the motor.
Replace turntable motor.
Oven can program but
timer does not start.
Defective circuitry of Start function
of Main P.C.B Ass’y.
Loose lead wires.
Check circuitry of Start function
of Main P.C.B Ass’y and replace if
defective.
Adjust or repair loose wires.
