Table of Contents
Advertisement
R990K(W)
CHAPTER 7.
R990K(W)
TROUBLESHOOTING GUIDE
[1] FOREWORD
When troubleshooting the microwave oven, it is helpful to follow the
Sequence of Operation in performing the checks. Many of the possible
causes of trouble will require that a specific test be performed. These
tests are given a procedure letter which will be found in the "Test Pro-
cedure"section.
[2] CHART
TEST PROCEDURE
CONDITION
Home fuse blows when power
supply cord is plugged into wall
outlet.
Fuse M8A blows when power
cord is plugged into wall outlet.
Display does not show anything
when power cord is first plugged
into wall outlet.
OFF
CONDITION
Display does not operate properly
when STOP/ CLEAR pad is
touched. (The time of day should
appear on the display with beep
sound during normal condition.)
Oven lamp does not light with
door opened.
Oven lamp does not light at all
Oven lamp light, but turntable
COOKING
motor does not operate.
CONDITION
Cooling fan motor does not operate.
The oven stops after1 minute.
Oven does not go into a cook cycle,
when START pad is touched.
Low or no power is produced
during microwave cooking (The
food is heated incom-pletely or
not heated at all)
(MICROWAVE)
Extremely uneven heating is
produced in oven load (food).
Function of variable cooking does
not operate properly except
HIGH power.
CONV
indicator
heating element does not heat.
Temperature in the oven cavity is
lower or higher than preset.
(CONVECTION)
Convection cycle runs 1 minute
then the oven shuts down.
Convection cycle runs 3 min-
utes then the oven shuts down.
Oven is in the sensor cook-ing
condition but AH sensor does not
(AH. SENSOR)
end 1st. stage or does not stop
cooking cycle or the oven stops
soon.
A B C D E E E F G G H I J J J J K M N O O O O O O P Q
PROBLEM
lights,
but
Service Manual
IMPORTANT:
If the oven becomes inoperative because of a blown fuse F10A in the
upper latch switch - lower latch switch - monitor switch circuit, check
the upper latch switch, lower latch switch and monitor switch before
replacing the fuse F10A.
7 – 1
CK = Check / RE = Replace
L
RE CKCK CK RE
Hide quick links:
Advertisement
Table of Contents
