MICROWAVE OVEN
Troubleshooting & Technical Data
6-2
P
P
P
P
rr
rr
ii
ii
o
o
o
o
rr
rr
tt
tt
o
o
o
o
S
S
S
S
e
e
e
e
rr
rr
ii
ii
a
a
a
a
ll
ll
N
N
N
N
u
u
u
u
m
m
m
m
b
b
b
b
e
e
e
e
rr
rr
1
1
1
1
2
2
2
2
0
0
0
0
0
0
0
0
1
1
1
1
5
5
5
5
4
4
4
4
TROUBLESHOOTING AND TECHNICAL DATA
This section of the manual combines the Troubleshooting Guide with Technical Data. The troubleshooting table on
the following page lists the condition and problems, as well as which parts need to be replaced or checked and
which test procedures to follow. The test procedures on the pages following the troubleshooting table contain the
appropriate technical data needed for each test.
When troubleshooting the microwave oven, it will be helpful to follow the Detailed Operating Sequence when per-
forming 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 Procedure" portion of this troubleshooting guide.
See “How to Use This Troubleshooting Table” on following page.
Before continuing, take note of the
WARNING
and Important Notes below.
-
MICROWAVE OVENS CONTAIN CIRCUITRY CAPABLE OF PRODUCING VERY HIGH VOLTAGE AND CUR-
RENT. CONTACT WITH THE FOLLOWING COMPONENTS MAY RESULT IN SERIOUS PERSONAL INJURY
OR DEATH:
•
TRANSFORMER
•
RECTIFIER
•
HIGH VOLTAGE HARNESS
•
MAGNETRON
•
CAPACITOR
-
TO AVOID ELECTRIC SHOCK DURING TROUBLESHOOTING, NEVER TOUCH ANY PART OF THE ELEC-
TRICAL CIRCUIT WITH HANDS OR UNINSULATED TOOLS WHILE THE POWER IS CONNECTED.
-
BEFORE SERVICING THE MICROWAVE OVEN, THE CAPACITOR MUST BE DISCHARGED BY SHORTING
THE CONNECTING LEAD OF THE RECTIFIER AGAINST THE CHASSIS WITH AN INSULATED SCREW-
DRIVER. FAILURE TO FOLLOW THIS STEP COULD RESULT IN SERIOUS PERSONAL INJURY OR
DEATH.
NOTE: THE CAPACITOR REMAINS CHARGED APPROXIMATELY 60 SECONDS AFTER THE
OVEN IS SWITCHED OFF. WAIT FOR 60 SECONDS, THEN SHORT THE CAPACITOR TO THE CHASSIS.
IMPORTANT NOTE:
If the oven becomes inoperative because of a blown monitor fuse, defective monitor switch,
interlock switch or door sensing switch, the complete Latch Hook/Switch Assembly must be
replaced. See part #802955 in the Service Parts Price List.
IMPORTANT NOTE:
When troubleshooting, it may be necessary in some cases to supply power to the unit with
the outer cabinet case removed. In this event:
1.
Disconnect the power supply cord, and then remove outer cabinet case.
2.
Open the door and block it open.
3.
Discharge high voltage capacitor.
4.
Disconnect the leads to the primary of the power transformer.
5.
Ensure that the leads remain isolated from other components and oven chassis by
using insulation tape.
6.
Only after performing the five steps listed above should the power supply cord be recon-
nected.
When the testing is completed:
1.
Disconnect the power supply cord, then remove outer case.
2.
Open the door and block it open.
3.
Discharge high voltage capacitor.
4.
Reconnect the leads to the primary of the power transformer.
5.
Reinstall the outer cabinet.
6.
Reconnect the power supply cord after the outer case is installed.
7.
Run the oven and check all functions.