Servicing - Sharp R-9320 Service Manual

SERVICING
TROUBLESHOOTING GUIDE
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 Procedures" section.
INPORTANT: If the oven becomes inoperative because of a
blown fuse in the upper latch-monitor-lower
latch switch circuit,
check the upper
and
lower latch switches and monitor switch be-
fore
replacing the fuse.
PROBLEM
POSSIBLE CAUSE
I
TEST PROCEDURE OR
'
CORRECTION
OFF CONDITION
I
I
I
1
Home fuse blows when power cord
is plugged into wall receptacle.
Shorted wire in power cord or wire harness.
1 Replace cord or check wiring.
1
I
Oven fuse blows when power
j Shorted wire in power cord or wire harness, Replace power cord or check and
j
, cord is plugged into wall receptacle. repair wire harness.
J
Defective monitor switch. ' Procedure G.
I
I
88:88 and all indicators do not
No power at outlet.
Check home fuse.
I
appear in display when power cord
/
.
is first plugged into wall outlet.
Blown oven fuse. Procedure H.
Open wire in power cord, wiring harness,
or wtring between control panel assembly
units.
Replace or repair wiring.
Defective control unit. Procedure N.
Display does not operate properly
when CLEAR key is touched.
Defective key unit.
~---
Defective control unit.
Procedure N.
Procedure N.
Defective stop switch. Procedure L.
-__-----.- - .-
Oven lamps do not light
with
No power in home.
Check wall outlet.
door opened.
Open
wire in power cord or wire harness. Replace same or repair wiring.
Defective oven lamp. Replace.
Defective lower latch switch.
Procedure F.
Open or loose wire connectlon to the
above components.
Check wiring.
_.- - -___ -
Blown oven fuse.
Procedure H.
__. -- -~__ _ ~-~ ~___ _. _. ___-~ -~ -..__-
28