AIWA ZL70
Manual de Servicio

NOTE 1. Forced
When across

ON

BEFORE

STARTING of electrolytic

REPAIR capacitor
uses though

discharge
is going

of power
relay circuit

supply

block
supply block, If repair electric potential is kept charged the

repair

to be attempted capacitors

in the set that 102) even

in the power cord

the electrolytic defect to prevent

(C101,

AC power

is removed.

is attempted

in this

condition,

secondary In order

can occur. the secondary trouble, perform the following measures before starting repair work.

Discharae -.
Remove Connect has clips wire

wocedure
the AC power a discharging at both ends. cord. resistor Connect at an end of lead the other wire that

I

II
II MAIN C.B

end of the lead

to metal

chassis. end (+VH) end of the discharging of C101. (For resistor two to the

Contact positive Contact @to way. Check

the other (+) side the same the negative (For that two

seconds) as step

of the discharging (-VH) of C102

resistor

(-) side

in the same

seconds) across C101 and C102 has decreased @ L
1

voltage using

1 V or less

a multimeter

or an oscilloscope.

@

Select

a discharging voltage

resistor (V)

referring

to the following

table.

Fig-1

Charging

Discharging Rated power (W) Parts number resistor (Q) 3 5 C102) of the electrolytic on schematic capacitors diagram 87-AOO-247-090 87-AOO-232-090 can change before depending on the models. work. Be sure to check the

(Clol,
25-48

102)

100
220 numbers (C101,

49-140
Note:

The

reference

reference

numbers

of the charging

capacitors

starting

the discharging

2.

Check
Be sure confirming

items
to check that

before

exchanging
items before

the

MICROCOMPUTER
the MICROCOMPUTER. Exchange the MICROCOMPUTER after

the following

exchanging is surely

the MICROCOMPUTER

defective.

2-1.

Regarding When

the

HOLD terminal

terminal (INPUT) is �L�,

of the

MICROCOMPUTER is �H�, be turned the MICROCOMPUTER on. Therefore, be sure is judged to check to be operating voltage of

the HOLD When terminal

of the MICROCOMPUTER the main power cannot

correctly. the HOLD When

this terminal before

the terminal

exchange. is not defective, the abnormality the HOLD circuit terminal can also go �L� when the POWER AMPLIFIER to �L�. has any

the MICROCOMPUTER that triggers

abnormalities

detection

on the MAIN

C. B. that

sets the HOLD

terminal

q

Good

or no good

judgement
power. power

of the MICROCOMPUTER

@
@

Turn

on the AC main that the main

Confirm not.

is turned

on and the HOLD

terminal

of the MICROCOMPUTER

keeps

the �H�

level

or

@

When

the HOLD

terminal

is �L� level,

the abnormality

detection

circuit

is judged

to be working

correctly

and the

MICROCOMPUTER

is judged

to be good.

�.�

.�.
FRONT C.B

I
i

r
I CON601

.�. �.�.
MAIN C.B

�.�
(@J

-�

MICROCOMPUTER

I PIN101 A $) �

In some

models,

it is PIN

OVER

LOAD

DET

POWER

AMP

POWER

AMP

POWER PIN �.� number is different upon microprocessor. .�. � . .�. � .�. � .�.

SUPPLY

depending

�

..

Fig-2-1

�5�