Chapter 7. Troubleshooting Guide; Foreword; Chart - Sharp R-20A1(S)VN Service Manual

CHAPTER 7.
TROUBLESHOOTING GUIDE
R218L(W)

[1] FOREWORD

When troubleshooting the microwave oven, it is helpful to follow the
Sequence of Operation in performing the checks. Many of the possible
tests are given a procedure letter which will be found in the "Test Pro-
cedure" section.

[2] CHART

TEST PROCEDURE
DEFECTIVE PARTS
PROBLEM
CONDITION
Home fuse blows when pow-
ersupply cord is plugged into
wall outlet.
OFF
CONDITION
FUSE T6.3A blows when
power supply cord is plug-
ged into wall outlet.
Oven does not start when
the timer is set
Oven lamp does not light
(Other function is normal.)
Fan motor does not operate.
(Other function is normal.)
Turntable motor does not
operate. (Other function is
normal.)
Oven or any electrical parts
ON
does not stop.
CONDITION
Oven seems to be operating
but little or no heat is pro-
duced in oven load. (Micro-
wave power level is set at
HIGH)
Oven does not seems to be
operating
MED HIGH, MED, MED
LOW or LOW is set. (Oven
operates properly at HIGH.)
Oven goes into cook cycle
but shuts down before end
of cooking cycle.
A B C
POSSIBLE CAUSE
AND
properly when
IMPORTANT:
If the oven becomes inoper ative because of a blown fuse T6.3A in the
monitored latch switch - relay RY1 - timer switch - monitor switch cir-
cuit, check the monitored latch switch, relay RY1, timer switch and
monitor switch before replacing the fuse T6.3A.
D E E E F J J G G H
CK
7 – 1
L M
RE CK CK RE CK CK CK CK CK
R-20A1(S)VN
I