SAMSUNG max460 Troubleshooting

Samsung Electronics 6-1

6. Troubleshooting

6-1 Amplifier

6-1-1 Power Malfunction

Front PCB µ-com VDD(5V)

normal?

UIC1 pin no. 18,47,90

Replace RIC1

Main PCB RIC1(BA3950) IN: 23V

Input voltage normal?

Yes

Check the Power PCB;
RD7,8,13(1N5392)

Yes

Front PCB

Does UX1(12MHz)

oscillate ?

FRONT PCB PWR-SENS

voltage normal ?

(pin no. 27 ; 5V)

Check the Main PCB
RD16,RR10,11,12,RC12
RD9

Yes

Front PCB

When the power is

ON 'H' displays

at pin no. 5 ?(5V)

Yes

Connect Front PCB and Main PCB.

Check the connector Main PCB.

Wafer MCW2

No

Replace µ-com.

Yes

No

No

No

No

Check the Power PCB : P/T, FUSE

No

6-2 Samsung Electronics

Yes

AQ103L,R Base B+ ?

Is Mute selected ?

Headphone Jack short ?

Remove it with Remocon.

Replace Headphone jack
soldering condition.

Main PCB AIC101

(STK4121,4141,4181-Option)

pin no. 9,11,12,14

B+,B- circuits

Check the B+ power
source part in RD1(PBL403),
RC2,3 and RIC1.

Yes

Confirm for TR short
replace it.

Check if the output line is
short.

No

No

No

No

Yes

Yes

Troubleshooting

6-1-2 No Output

Samsung Electronics 6-3

IZD1(8.2V) Voltage ok ?

Yes

Check TUNER IC(LA1836)

pin no.10 ; 8.2V
pin no.14 ; 7.2V

AM ; 0V ?

Yes

LC72131

CONTROL ok?

Yes

FM VT

LC72131 pin no.20

1.7V 7.5V ?

Yes

AM VT

LC72131 pin 20

Check the LC72131

CONTROL ok?

Yes

Yes

Check HIC1

pin 20 ?

LPF1,2

output ok?

Check TDA7318 function ok?

Check FEP interior

pattern, and any line

disconnections.

 1) Power impaired

so repair defects.

2) LC72131 Oscillator
(HX1 : 7.2MHz) ok ?

3) System line ok?

No

Yes

Check for µ-com IC

Replace LC72131

No

HZD1 (5.6V) Voltage ok?

HIC1 (LC72131) FM/AM BAND

Switching ok?

No

No

No

No

No

No

No

0.9V 7V

?

Power section defective

RIC1(BA3950) Voltage ok?

PIN NO.8 : 12V

Check the voltage ok ?

No

No

Troubleshooting

6-1-3 Tuner Malfunction (FM/AM)

6-4 Samsung Electronics

Yes

Connector inserted

correctly?

No

Yes

Check voltage : AC 4.8V

at FRONT-PCB FLT?

No

Check Main-PCB Front PCB
connection and the voltage of
MCW2, pins1,2(AC4.8V)

Yes

Check voltage at UIC1

pin no. 48(-30V)

No

Check the voltage of RD3(-30V)

Reinsert the connector.

Replace UIC1

6-1-4 V.F.D Malfunction

Troubleshooting