LG MB-339MB, Service Manual

Page: 23 / 38

TROUBLE SHOOTING
WHEN YOU GET A COMPLAINT FROM YOUR CUSTOMER, EVALUATE THE COMPLAINT CAREFULLY. IF
THE FOLLOWING SYMPTOMS APPLY, PLEASE INSTRUCT THE CUSTOMER IN THE PROPER USE OF THE
MICROWAVE OVEN. THIS CAN ELIMINATE AN UNNECESSARY SERVICE CALL.
5-13
CAUTIONS
1. Check grounding before checking for trouble.
2. Be careful of the high voltage circuit.
3. Discharge the high voltage capacitor. (See page 2-1)
4. When checking the continuity of the switches or of the high voltage transformer, disconnect one lead wire
from these parts and then check continuity with the AC plug removed. To do otherwise may result in a
false reading or damage to your meter.
5. Do not touch any part of the circuit on the PCB since static electric discharge may damage this control
panel.
Always touch yourself to ground while working on this panel to discharge any static charge built up in your
body. (Micom model only)
CONDITION
Microwave oven
does not work.
Inserting many plugs into one
outlet and using them at the
same time.
(blown fuse or breaker)
Microwave oven plug is not
inserted tightly.
Output power is too low. Low AC input voltage.
Food temperature is too low.
Using metallic ware and
allowing it to touch the oven
wall.
Sparks occur.
Inconsistent intensity of
microwave by their
characteristics.
1. Use plastic wrap or lid.
2. Stir once or twice while
cooking soup, cocoa or
milk, etc.
Uneven cooking.
Ceramic ware trimmed in
gold or silver powder is used.
Avoid using other electrical
appliances when you use the
microwave oven.
Insert microwave oven plug
securely.
Use the microwave oven at
adequate line voltage.
This is not a defect.
It is possible that the food
should be cooked for a
longer time.
Do not use metallic ware for
cooking except that noted in
the cooking guide.
Do not use any type of
cookware with metallic
trimming.
CAUSE REMEDY