Sharp r-8580 manual Test Procedures Cont’O, Letter, Component, Touch Control Panel Assembly Test

TEST PROCEDURES (CONT’O)

PROCEDURE
LETTER	COMPONENT	TEST

TOUCH CONTROL PANEL ASSEMBLY TEST

The touch control panel consists of circuits including semiconductors such as LSI, ICs, etc. Therefore, unlike conventional microwave ovens, proper maintenance cannot be performed with only a voltmeter and ohmmeter. In this service manual, the touch control panel assembly is di-

vided into three units Control Unit, Key Unit and Relay Unit and troubleshooting by unit re- placement is described according to the symptoms indicated.

1. Key Unit.

The following symptoms indicate a defective key unit. Replace the key unit.

a)When touching the pads, a certain pad produces no signal dt all.

b)When touching a number pad, two figures or more are displayed.

c)When touching the pads, sometimes a pad produces no signal. 2. Control Unit

The following symptoms indicate a defective control unit. Replace the control unit. 2-1 In connection with pads.

a)When touching the pads;a certain group of pads do not produce a signal.

b)When touching the pads, no pads produce a signal.

2-2 In connection with indicators

a)At a certain digit, all or some segments do not light up.

b)At a certain digit, brightness is low.

c)Only one indicator does not light up.

d)The corresponding segments of all digits do not light up; or they continue to light up.

e)Wrong figure appears.

f)A certain group of indicators do not light up.

g)The figure of all digits flicker.

2-3 Other possible troubles caused by defective control unit.

a)Buzzer does not sound or continues to sound.

b)Clock does not operate properly.

c)Cooking is not possible.

d)Proper temperature measurement is not obtained.

Note: When defective components, the Control Unit, Key Unit or Relay Unit are replaced, the defective part or parts must be properly packed for return in the shipping carton, with its cushion material, in which the new replacement part was shipped to you.

(RD82SOl U)

P KEY UNIT TEST

If the indicator does not respond to touching a key Pad use the following matrix and place a jumper wire between the proper pin connections making momentary contact with the cable connector disconnected from the control unit.

If the indicator responds and oven goes into operation, the key unit was faulty. If there is no response, replace the control unit,

-9

3

160°C

I

4

150°C

I

3

13o”c2

70°C

I

1

40%

I

5-l

I

0

250°C

9

230-C

8

220°C

7

200%

6

180%

LowM’

HIGH

MED HIGH

MED

MU) Low

LOW

F

CLOCK

1 CLEAR

1 COOK

1

HOU)

DI

I

1 KEY UNIT ‘]

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