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After correcting the original service problem, perform the following 
safety checks before releasing the set to the customer:

1.  Check the area of your repair for unsoldered or poorly soldered 

connections. Check the entire board surface for solder splashes and 
bridges.

2.  Check the interboard wiring to ensure that no wires are “pinched” or 

touching high-wattage resistors.

3.  Check that all control knobs, shields, covers, ground straps, and 

mounting hardware have been replaced. Be absolutely certain that 
you have replaced all the insulators.

4.  Look for unauthorized replacement parts, particularly transistors, 

that were installed during a previous repair. Point them out to the 
customer and recommend their replacement.

5.  Look for parts which, though functioning, show obvious signs of 

deterioration. Point them out to the customer and recommend their 
replacement.

6.  Check the line cords for cracks and abrasion. Recommend the 

replacement of any such line cord to the customer.

7.  Check the B+ and HV to see if they are specifi ed values. Make sure 

your instruments are accurate; be suspicious of your HV meter if 
sets always have low HV.

8.  Check the antenna terminals, metal trim, “metallized” knobs, screws, 

and all other exposed metal parts for AC leakage. Check leakage as 
described below.

Leakage Test
The AC leakage from any exposed metal part to earth ground and from 
all exposed metal parts to any exposed metal part having a return to 
chassis, must not exceed 0.5 mA (500 microamperes). Leakage current 
can be measured by any one of three methods.

1.  A commercial leakage tester, such as the Simpson 229 or RCA 

WT-540A. Follow the manufacturers’ instructions to use these 
instructions.

2.  A battery-operated AC milliammeter. The Data Precision 245 digital 

multimeter is suitable for this job.

3.  Measuring the voltage drop across a resistor by means of a VOM 

or battery-operated AC voltmeter. The “limit” indication is 0.75 V, 
so analog meters must have an accurate low voltage scale. The 
Simpson’s 250 and Sanwa SH-63TRD are examples of passive 
VOMs that are suitable. Nearly all battery-operated digital multimeters 
that have a 2 VAC range are suitable (see Figure A).

How to Find a Good Earth Ground
A cold-water pipe is a guaranteed earth ground; the cover-plate retaining 
screw on most AC outlet boxes is also at earth ground. If the retaining 
screw is to be used as your earth ground, verify that it is at ground by 
measuring the resistance between it and a cold-water pipe with an 
ohmmeter. The reading should be zero ohms.

If a cold-water pipe is not accessible, connect a 60- to 100-watt trouble- 
light (not a neon lamp) between the hot side of the receptacle and the 
retaining screw. Try both slots, if necessary, to locate the hot side on the 
line; the lamp should light at normal brilliance if the screw is at ground 
potential (see Figure B).

Trouble Light

AC Outlet Box

Ohmmeter

Cold-water Pipe

Figure A. Using an AC voltmeter to check AC leakage.

Figure B. Checking for earth ground.

To Exposed Metal
 Parts on Set

AC Voltmeter
(0.75 V)

Earth Ground

0.15 

µ

F

1.5 

k

Ω

The units in this manual contain a self-diagnostic function. If an error occurs, the STANDBY/TIMER LED will automatically begin to flash. The number 

of times the LED flashes translates to a probable source of the problem. A definition of the STANDBY/TIMER LED flash indicators is listed in the 

instruction manual for the user’s knowledge and reference. 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/TIMER LED will flash a set number of times to indicate the possible cause of the problem. If there is more than 

one error, the LED will identify the first of the problem areas.

Results for all of the following diagnostic items are displayed on screen. If the screen displays a “0”, no error has occurred.

Power�does�not�turn�on��

Does�not�light�

_______� •� Power�cord�is�not�plugged�in.�

•� Fuse�is�burned�out�(F6000).�(A�Board)�

•� Power�does�not�come�on.�

•� No�power�is�supplied�to�the�TV.�
•� AC�Power�supply�is�faulty.�

+B�Overcurrent�(OCP)*�

2�times�

2:0�or�2:1� •� H.OUT�(Q5001)�is�shorted.�(D�Board)�

•� +B�PWM�(Q5201)�is�shorted.��

(D�Board)�

•� Power�does�not�come�on.�
•� Load�on�power�line�shorted.�

Low�+B�Overvoltage�(OVP)�

3��times�

3:0�or�3:1� •� IC6503�is�faulty.�(D�Board)��

•� Has�entered�standby�mode.�

Vertical�Deflection�Stopped�

4�times�

4:0�or�4:1� •� 15V�is�not�supplied.�(D�Board)�

•� IC5101�is�faulty.�(D�Board)�

•� Has�entered�standby�mode�after�

Horizontal�raster.�

•� Vertical�deflection�pulse�is�stopped.�
•� Power�line�is�shorted�or�power�

supply�is�stopped.�

White�Balance�Failure�

(not�balanced)�

5�times�

5:0�or�5:1� •� Video�OUT�(IC9101,�IC9201,�IC9301)�

is�faulty.�(CR,�CG,�CB�Board)�

•� CRT�drive�(IC0401)�is�faulty.��

(A�Board)�

•� G2�is�improperly�adjusted.**�

•� No�raster�is�generated.�

•� CRT�cathode�current�detection�

reference�pulse�output�is�small.�

LOW�+B�OCP/OVP�

(overcurrent/overvoltage)***�

6�times�

6:0�or�6:1� •� +5�line�is�overloaded.��

(A�and�BH�Boards)�

•� +5�line�is�shorted.�(A,�BH�Boards)�

•� IC303�is�faulty.�(A�Board)�

•� No�picture�

Horizontal�Deflection�

Stopped�

7�times�

7:0�or�7:1� •� Q5006�is�broken�(D�Board)�

•� IC452�is�faulty�(A�Board)�

•� No�picture�

Audio�Protection�

8�times�

8:0�or�8:1� •� +�or�-�22V�audio�supply�is�not�

presentó Check�PS600�&�PS601�

•� Audio�AMP�is�damaged�IC601�on�

A�Board�

•� No�picture�

Zero�Crossing�Detector�

9�times�

9:0�or�9:1� •� Q6301,�PH6301�circuit�are�faulty��

(��Board)�

•� No�picture�

HV�Protection�

10�times�

10:0�or�

10:1�

•� Q8014�or�Q8013�have�shorted�replace�

along�with�R8051�on�D�Board�

•� IC8005�is�damaged�(D�Board)�

•� No�picture�

�

*� If�a�+B�overcurrent�is�detected,�stoppage�of�the�vertical�deflection�is�detected�simultaneously.�The�symptom�that�is�diagnosed�first�by�the�

microcontroller�is�displayed�on�the�screen.�

**�Refer�to�Screen�(G2)�Adjustment�(Fine�Adjustments)�in�Section�2�of�this�manual.�

***�If�STANDBY/STEREO�LED�flashes�six�(6)�times,�unplug�the�unit�and�wait�10�seconds�before�performing�the�adjustment.�

STAND BY Indicator

TIMER Indicator

+B Overcurrent 

2 times

Low +B Overvoltage 

3 times

Vert. Deflection Stopped 

4 times

White Balance Failure 

5 times

Low +B OCP/OVP 

6 times

Horiz. Deflection Stopped 

7 times

Audio Protection 

8 times

Zero Crossing Detector 

9 times

HV Protection 

10 times

Release of TIMER STAND BY indicator blinking
The TIMER/STANDBY indicator blinking display is released by turning OFF the power switch on the TV main unit or removing the plug from the power.

Self-Diagnosis Screen Displays
In cases of malfunctions where it is not possible to determine the symptom such as when the power goes off occasionally or when the screen 
disappears occasionally, there is a screen display on whether the malfunction occurred or not in the past (and whether the detection circuit operated or 
not) in order to allow confi rmation.

Screen Display Method
Quickly press the remote command button in the following order from the standby state.

  Display  

  Channel  5   

  Sound Volume* 

_

  

  Power ON 

 

 

 

 

 

*Note that this differs from entering the service mode (sound volume  +  )

 

Numeral “0” 

means that no fault was detected.

Numeral “1” 

means a fault was detected one 
time only.

 2: 

+B 

OCP 

0

 3: 

+B 

OVP 

0

 4: 

VSTOP 

0

 5: 

AKB 

1

 6: 

LOWB 

0

 7: 

H-STOP 

0

 8: 

AUDIO 

0

 9: 

ZCD 

0

 10: 

HV 

PROT 

0

 101: 

WDT 

24

Self-Diagnosis Screen Display
The results display is not automatically cleared.  In case of repairs and after repairs, check the self-diagnosis screen and be sure to return the results 
display to “ 0 ”. 
If the results display is not returned to “ 0 ” it will not be possible to judge a new malfunction after completing repairs.

1.  Power off (Set to the stand by mode.)
2.   Display  

  Channel  5   

  Sound Volume  +   

  Power ON (Service Mode) 

3.  Channel  8   

   ENTER  (Test reset = Factory preset condition)

Method of Ending Self Diagnosis Screen
When ending the self-diagnosis screen completely, turn the power switch OFF on the remote commander or the main unit.

+B overcurrent (OCP) 
Occurs when excessive current fl ows through R6812. The increase in voltage across Q6803 causes it to turn on which sends a high signal to the 
micro. 

+B overvoltage (OVP) 
IC6801 detects +B OVP condition and turns on Q6802. This sends a high signal to the micro and also shuts down the AC relay.

V-STOP 
Occurs when an absence of the vertical defl ection pulse is detected by pin 56 of IC452 (A Board). Power supply will shut down when waveform interval 
exceeds 2 seconds. 

White Balance Failure
If the RGB levels* do not balance within 2 seconds after the power is turned on, this error will be detected by IC452 (A Board). TV will stay on, but 
there will be no picture.

*(Refers to the RGB levels of the AKB detection Ref pulse that detects 1K).

Low B OCP/OVP
Occurs when set 5V is out.
     Also check for :  + 135V line shorted
 

  

+ 135V line is going over 145V

Horizontal Defl ection Stopped
Occurs when either: 
 

1) a +B overcurrent is detected (Q6803), or 

 

2) IC452 (A Board) is damaged.

3

1

2

R5104

R5105

R5125

Q5018

RY6000

Q6102

Q451

Q452

D452

D6803

D6505

D453

R6812

D6805

R6803

IC6801 

Q6802

1K-PROT2

+B OCP

+BVOP

5V 

+B OCP

2

1

3

4

IC5007

VDY-

CRT

IC452

Y/C JUNGLE

SCL

SDA

AKB

VPROT

HPROT

IC702

MAIN MICRO

A

CLKO

DATO

AC RLY

LOW B ERR

OVP

OCP

STR
STBY-LED

STBY-LED

P_SW(-)

IC303

5V

+B

+B

+B

BH

A

D

D

A

2

14

57

56

58

53

52

28

31

69

43

44

45

48

3

1

2

G