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To Exposed Metal 

Parts on Set

0.15  F

1.5 K 

Ω

AC

Voltmeter

(0.75 V)

Earth Ground

Trouble Light

AC Outlet Box

Ohmmeter

Cold Water Pipe

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 milliampmeter. 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).

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

Figure B. Checking for earth ground.

+B Overcurrent (OCP)

2 times

+B Overvoltage (OVP)

3 times

Vert. Deflection Stopped

4 times

White Balance Failure

5 times

Low B OCP/OVP

6 times

Horiz. Deflection Stopped

7 times

Stopping the STANDBY/STEREO LED Flash
Turn off the power switch on the TV main unit or unplug the power cord from the outlet to stop the STANDBY/STEREO LAMP from fl ashing.

Self-Diagnostic Screen Display
For errors with symptoms such as “power sometimes shuts off” or “screen sometimes goes out” that cannot be confi rmed, it is possible to bring up 
past occurrences of failure on the screen for confi rmation.

The units in this manual contain a self-diagnostic function. If an error occurs, the STANDBY/STEREO 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/STEREO 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/STEREO 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.  No error has occurred if the screen displays a “0”.

Power does not turn on 

Does not light 

 

•  Power cord is not plugged in. 

•  Power does not come  on.

 

 

 

•  Fuse is burned out F6001 (A Board). 

•  No power is supplied to the TV.

 

 

 

   

•  AC power supply is faulty.

+B Overcurrent (OCP) 

2 times 

2:0 or 2:1 

•  H.OUT (Q5030) is shorted (D Board). 

•  Power does not come on.

(See Note 1) 

 

 

•  +B PWM (Q5003) is shorted (D Board). 

•  Load on power line is shorted.

 

 

 

•  IC9001, IC9002, IC9003 is shorted (C Board).

+B Overvoltage (OVP) 

3 times 

3:0 or 3:1 

•  IC6505 is faulty (D Board). 

•  Has entered standby mode.

Vertical Defl ection Stopped 

4 times 

4:0 or 4:1 

•  ± 15V is not supplied (D Board). 

•  Has entered standby state after

 

 

 

•  IC5004 is faulty (D Board). 

  horizontal raster.

 

 

 

   

•  Vertical defl ection pulse is stopped.

 

 

 

   

•  Power line is shorted or power

 

 

 

   

  supply is stopped.

White Balance Failure 

5 times 

5:0 or 5:1 

•  Video OUT (IC9001-IC9003) is faulty (C Board).  •  No raster is generated.

(not balanced) 

 

 

•  CRT drive (IC201) is faulty (A Board). 

•  CRT Cathode current detection

 

 

 

•  G2 is improperly adjusted (See Note 2). 

  reference pulse output is small.

 

 

 

LOW B OCP/OVP 

6 times 

6:0 or 6:1 

•  +5 line is overloaded (A, B Boards). 

•  No picture.

(overcurrent/overvoltage) 

 

 

•  +5 line is shorted (A, B Boards).

(See Note 3) 

 

 

•  IC6007 is faulty (A Board).

Horizontal Defl ection Stopped 

7 times 

7:0 or 7:1 

   

•  No picture.

Note 1: If a +B Overcurrent is detected, stoppage of the Vertical Defl ection is detected simultaneously.  The symptom that is diagnosed fi rst by the microcontroller is displayed on screen.
Note 2: Refer to Screen (G2) Adjustment in Section 2-5. of this manual.
Note 3: If STANDBY/STEREO LED fl ashes six (6) times, unplug the unit and wait 10 seconds before performing the adjustment.

*  One fl ash count is not used for self-

diagnostic.

Handling of Self-Diagnostic Screen Display
Since the diagnostic results displayed on the screen are not automatically cleared, always check the self-diagnostic screen during repairs. When you 
have completed the repairs, clear the result display to “0”.
Unless the result display is cleared to “0”, the self-diagnostic function will not be able to detect subsequent faults after completion of the repairs.

Clearing the Result Display
To clear the result display to “0”, press buttons on the Remote Commander sequentially when the diagnostic screen is displayed, as shown below:

 

Channel  8  

  ENTER

Quitting the Self-Diagnostic Screen
To quit the entire self-diagnostic screen, turn off the power switch on the Remote Commander or the main unit.

+B Overcurrent (OCP) 
Occurs when an overcurrent 
(more than 6A) on the +B 
(135V) line is detected by 
R6598/R6591. It will cause 
Q6520 to turn on and force the 
AC relay to turn off through 
Q6532 and Q6530.

+B Overvoltage (OVP) 
Occurs when 1) overvoltage 
(more than +140V) on the 
+B (135V) line is detected by 
IC6505, or 2) an overvoltage 
(more than 7.5 V) on the unreg 
7V line is detected by D6014.  
The AC relay will turn off 
through Q6532 and Q6530.

Vertical Defl ection Stopped 
Occurs when an absence of 
the vertical defl ection pulse 
is detected by IC201. 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 IC201. 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 Error
Occurs when set 5V is out.

Horizontal Defl ection Stopped
Occurs when either: 1) a +B overcurrent is detected (IC5007), or 2) overheating is detected (Thermistor TH5002).

Numeral “0” means that no fault 
was detected.

Numeral “1” means a fault was detected 
one time only.

To Bring Up Screen Test
In standby mode, press buttons on the Remote Commander sequentially, 
in rapid succession, as shown below:

DISPLAY   

 Channel  5   

 Sound volume  -   

 Power ON.

AKB

VPROT

HPROT

SCL

SDA

IC701

MAIN UCOM

STBY LED

HA

STR

STBY-LED

OCP

OVP

LOW B ERR

AC RLY

CLKO

DATO

29

30

69

43

45

44

48

Q6532

Q6530

D6537

D6501

Q6527

RY6501

SET ON

200V OCP

+B OCP

OVP

D8027

D8003

0

0

I

UNREG 7V

D6014

D6018

SET 5V

26

25

58

35

34

CRT

VDY -

R5125

R5104

R5105

IC5007

2

14

Q5018

I5V

2

1

3

OVP

Q6522

STBY 5V

Q6524

Q6521

IC6505

+B OVP

+B

Q6520

IC6007

IC201

Y/C JUNGLE

D

A

A

A

D

2

1

Chassis 

Assembly

1

1

  CAUTION! - Heat sink on IC5004 is -15V.  Care must be 

taken not to allow heat sink to touch any other components.

2

  Lift lever up on the right and left sides of the chassis bracket 

and gently pull the chassis assembly away from the bezel.

Remove +BVTP 4 x 16 screws from
areas indicated with a circle.

Rear Cover

1

  Pull up and rotate both the A and D Boards in order to 

service the unit.