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– 3 –

Diagnosis

Item

Description

• No Power

• +B overcurrent

(OCP)

• Vertical NG.

• IK (AKB)

• Supply Voltage

Protection

Detected

Symptoms

• Power does not turn on.
• No power is supplied to the

TV.

• AC power supply is faulty.

• Power does not turn on.
• Load on power line is

shorted.

• Has entered standby state

after horizontal raster.

• Vertical deflection pulse is

stopped.

• Power line is shorted or

power supply is stopped.

• No raster is generated.
• CRT cathode current

detection reference pulse
output is small.

• No power supply to CRT

ANODE.

• No RASTER is generated.

No. of times

STANDBY

Indicator flashes

Does not light

2 times

4 times

5 times

8 times

Diagnostic Result

on screen display

—

2:0

2:1 ~ 255

4:0

4:1 ~ 255

5:0

5:1 ~ 255

8:0

8:1 ~ 255

Probable

Cause

Location

• Power cord is not plugged

in.

• Fuse is burned out (F4601)

(F Board)

• H.OUT (Q511) is shorted.

(A board)

• IC751 is shorted.

(C/CV Board)

• +13V is not supplied.

(A Board)

• IC503 voltage list is faulty.

(A Board)

• Video OUT (IC751) is faulty.

(C Board)

• IC001 is faulty. (A Board)
• Screen (G2) is improperly

adjusted.

• IC604 faulty.
• IC607 faulty.

The units in this manual contain a self-diagnostic function. If an error occurs, the STANDBY Indicator will automatically
begin to flash.
The number of times the STANDBY Indicator flashes translates to a probable source of the problem.If an error symptom
cannot be reproduced, the remote commander can be used to review the failure occurrence data stored in memory to
reveal past problems and how often these problems occur.

When an error occurs, the STANDBY Indicator will flash a number of times to indicate the possible cause of the
problem. If there is more than one error, the Indicator will identify the first of the problem areas.

Result for all of the following diagnostic items are displayed on screen. No error has occured if the screen displays a “0”.

The example above represents for 4 times blink

Lamp OFF 3 seconds 

Lamp ON 300ms

Lamp OFF 300ms

Standby indicator

– 4 –

[+B overcurrent $OCP%]

Occurs when an overcurrent on the +B(135V) line is detected by pin 97 of IC001 (A board).
If the voltage of pin 97 of IC001 (A board) is more than 4V, the unit will automatically go to
standby.

[V-PROTECT]

Occurs when an absence of the vertical deflection pulse is detected by pin 116 of IC001
(A board).

[IK $AKB%]

If the RGB levels* do not balance within 15 sec after the power is turned on, this error will be
detected by IC001 (A board). TV will stay on, but there will be 5 times LED blinking.

Occurs when IC001 internal HV protect detects an abnormal H-Pulse (frequency) due to
improper power supply to IC001. TV cuts off high voltage power of anode CRT. No picture will be
detected. eg: IC602, IC604 go faulty.

* (Refers to the RGB levels of the AKB detection Ref pulse that detects IK.)

A BOARD

IC001

Y/CHROMA JUNGLE

A BOARD

IC804

V.OUT

A BOARD

IC001

SYSTEM

A BOARD

IC003

MEMORY

FROM

C BOARD

IC751 PIN 5

IK

EHTO

RED LED

DISPLAY

SDA1

V.GUARD

SDA

5

F.B-PLS

3

116

45

97

7

A BOARD

FROM

Q816

COLLECTOR

30

POWER SUPPLY NG (+5V)
for VIDEO PROCESSOR

2 : 

000

3 :

N/A

4 :

000

5 :

001

8 :

002

101 :

N/A

"0" means no fault has been detected.

"1" means a fault has been detected.
"2" means two faults has been detected.

"N/A" means not available for this models.

SELF DIAGNOSTIC

5

8

1.

Display self diagnostic screen

[Display] t [Channel    ] t [Volume    ] t [Power / TV]

Note: The above must be performed while TV is on standby mode.

2.

Stop standby flash

i) Turn off power switch on main.
ii) Unplug power cord from the outlet.

3.

Clear fault result

In Self Diagnostic Screen, press, 

[Channel    ] t 

-

Note: Diagnostic results display on screen is not automatically cleared. Therefore,
clear result after completion of repair.

4.

Quit self diagnostic screen

Turn off power switch of remote commander or main unit.

– 5 –

2 Rear cover

1 Nine screws
     (+BVTP 4 

× 16)

1 Two screws
     (Washer Head) 
     (+P4x16)

– 6 –

1 Two hooks 

3 One screw

(+BVTP 3 x 12)

2 F Board

1 One screw
 (+BVTP 

3 

× 12

 Type2 

IT-3)

2 Two hooks 

6 One screw
 (+BVTP 

3 

× 12

 Type2 

IT-3)

5 Terminal bracket

3 One screw
 (+BVTP 

4 

× 12

 Type2 

IT-3)

4 Two screws
 (+BVTP 

3 

× 12

 Type2 

IT-3)

3 One screw
    (+BVTP 3 

× 12)

1 One screw
     (+BVTP 4 

× 16 Type2 IT-3)

4 One screw
    (+BVTP 3 

× 12)

2 Terminal bracket

5 hooks

3 F2 Board

1 J3 Board

2 Two screws
     (+BVTP 3 

× 12 Type2 IT-3)

2 F1 Board

1 Two hooks

3 One screws
     (+BVTP 3 

× 12 Type2 IT-3)

3 Four hooks

1 Five hooks

2 H7 Board

4 H4 Board