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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.

µ

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 fl ash. The number 
of times the LED fl ashes translates to a probable source of the problem. A defi nition of the STANDBY/TIMER LED fl ash 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.

Diagnostic Test Indicators
When an error occurs, the STANDBY/TIMER LED will fl ash 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 fi rst 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.

FRONT PANEL

TIMER/STANDBY indicator

Lamp OFF : 
3.0 seconds

Lamp ON : 0.3 seconds

Lamp OFF : 0.3 seconds

• EXAMPLE

Diagnosis Items 

Number of Blinks

+B overcurrent  

2 times

+B overvoltage

3 times

Vertical deflection stop

4 times

*

 One blink is not used for self-diagnosis.

Power not On 

0 

[Standby Power Supply System] 

Cannot turn on the power

  

F601 

open 

LED 

doesn’t blink

  

R607 

open

  

Q601 

short 

circuit

  

[Main 

Power 

Supply 

System}

 

 

IC601 and R612 are broken

  

VDR601 

short-circuit

+B OCP Detection 

2 times 

Short circuit of power supply in each circuit 

Goes to the standby mode 

2:  +B OCP 000

 

 

 

Short circuit of the +B line

+B OVP Detection 

3 times 

T603 pin 7 to pin 8 is open 

Goes to the standby mode 

3:  +B OVP 000

Vertical Defl ection Stop 

4 times 

IC 1509 (V OUT) is broken 

Raster goes to one line horizontally 

4: V Stop 000

 

 

Q1505 (V Pulse Buffer) is broken 

A and then video signal is muted.

Video Out Abnormality 

5 times 

Video Out, Q705, 732, 761, and others in C board 

STANDBY/TIMER LED blinks approx. 

5: AKB  000

Detection 

 

 

30 secs, then blinks for the diagnosis

Horizontal Defl ection Stop 

6 times 

C515, 516 open.  IC206 (YC Jungle) is broken. 

Raster does not appear. 

6: H Stop  000

Audio Abnormality 

8 times 

IC 406 (Audio amp.) is broken. 

The sound is not out. 

8: Audio  000

Detection 

 

PS401, 402 open 

Goes to the standby mode

Note:  000 the range of values for number of operations is 000 - 255.  For 256 or higher, the number remains as 255.

Release of TIMER/STANDBY 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  +  )

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 stanby 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.

2:  +B  OCP  000

Results

Diagnosis

000 the range of values for number of 
operations is 000-225.
For 256 or higher, the number remains 
at 255.

OCP 

Low B and +B line detect DET SHORT, and shut-down POWER ON RELAY. 

 

Reset by turning power on/off. 

 

In case of +B is loaded approx. 1.3A or more, microcomputer detects it via IC651. 

OVP 

In case of +B becomes approx. 150V or more, POWER ON RELAY shuts down and microcomputer detects it via IC651. 

 

Reset by turning power on/off just the same as OCP. 

V Stop 

In case of microcomputer detects 2 seconds or more interval of V Pulse, Reference Pulse turns off by turning off the picture 

 

signal in YC Jungle IC (IC206). 

 

After the picture signal turns off, V Pulse is regenerated 2 seconds or more, the picture signal turns on. 

AKB 

IK detection.  Makes LED blinking in case of microcomputer doesn’t detect IK returns of IC206 CXA2147Q 30 seconds or more. 

H Stop 

In case of HV becomes 33kV or more, IC502 detects it and shut-down H Drive Pulse. 

 

Microcomputer receives H Stop data from IC206 and makes LED blinking. 

Audio 

In case of DC component overlaps the output of Audio Amp., microcomputer detects it and makes LED blinking. 

 

Microcomputer forces to shut down the power. 

       

55

8

20

21

22

49
47
50

3

27

34

35

43

5. AKB

5. AKB

3. OVP

2. OCP

4. V.STOP (V Pulse)

Audio

IC002

mProcessor

IC206

CXA2147

YCJ

Q006

D1201

TIMER/STANDBY

IC004

EEPROM

IC502

HV Detector

Q1505

V Pulse Buffer

IC651

OVP Buffer
OCP Buffer

C Board

DC Detect

IC1509
V Drive

IC406

Audio AMP

6. H STOP

6. HV STOP

BUS

4

48

OVP DETECT

OCP DETECT