Sharp r-8580 manual Servicing, OFF Condjtion, Problem Possible Cause Test Procedure Correction

SERVICING

TROUBLESHOOTING

GUIDE

When

troubleshooting

the microwave

oven,

it

is

IMPORTANT:

lf

the

oven

becomes

inoperative

be-

helpfull

to

follow

the

Sequence

of

Operation

in

per-

cause

of a blown

fuse

in the

monitor

forming the checks. Many of the possible causes of

switch and upper latch switch circuit,

check the monitor switch and upper

trouble

will

require

that

a

specific

test

be

performed.

latch switch before replacing the fuse.

These

tests

are

given

a

procedure

letter

which

will

be

If

the

fuse

is

replaced,

the

monitor

found

in

the

“Test Procedure”section.

switch

should

be

replaced

at

same

time.

(RD8’ll

OZU)

PROBLEM

POSSIBLE

CAUSE

TEST

PROCEDURE

OR

CORRECTION

OFF CONDJTION

Home

fuse

blows

when

power

Shorted

wire

in

power

cord

or

wire

har-

Replace cord or check wiring.

cord

is

plugged

into

wall

recepta-

ness.

cle.

Fuse blows when power cord is

Shorted

wire

in

power

cord

or

wire

har-

Replace

power

cord or

check

plugged

into wall

receptacle.

ness.

and repair

harness.

Defective

monitor

switch.

Procedure

F.

88:88

do

not

appear

in

display

No

power

at

outlet.

Check

home

fuse.

when

power

cord

is

first

plugged

Blown

fuse.

Procedure

G.

into

wall outlet.

Blown

magnetron

temp.

fuse.

Procedure

H.

Defective thermal cut-out.

Procedure

I.

Open

wire in power

cord,

wiring

harness,

Replace or

repair

wiring.

or wrrrng between control panel assembly

units.

Defective

CPU

unit.

Procedure

0.

Defective

relay

unit.

Procedure

N.

Display

does not

operate

properly

Defective

key unit.

Procedure

P.

when

STOP/CLEAR

key

is

Defective

CPU

unit.

Procedure

0.

touched.

(B uzzer should

sound

Defective

relay

unit.

Procedure

N.

and time of day should

appear

in

display.)

Defective

stop

switch.

Procedure

E.

Oven lamp does not light with

No

power

in

home.

Check

wall

outlet.

door

opened.

, Open wire in power cord or wire harness. , Replace same or repair wir- 1

rng.

Defective

oven

lamp.

Replace.

Defective

upper

latch

switch.

-*

Procedure

E.

Blow fuse.

Procedure

G.

Defective thermal cut-out.

Procedure

I.

Defective

magnetron temp.

fuse.

Procedure

H.

Open

or

loose

wire

connection

to

the

Check

wiring.

above

components.

11