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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.

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

Numeral “0” means that no fault was detected.
Numeral “1” means a fault was detected one time only.

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 on the +B (115V) line is detected by pin 18 of IC301. If the voltage of pin 18 of IC301 is less than 1V when V.SYNC is more 
than seven verticals in a period, the unit will automatically turn off. 
Vertical Defl ection Stopped 
Occurs when an absence of the vertical defl ection pulse is detected by pin 17 of IC001.  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 IC301. TV will stay on, but there 
will be no picture.

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

Note that this differs from entering the Service Mode (Sound Volume  +  ).

IC301

Y/CHROMA JUNGLE

IC541

V. OUT

IC001

SYSTEM

IC003

MEMORY

IK IN

FROM

CRT

HP/PROTECT

SDA

FROM

IC521

PIN 7

18

IO-SDAT

O-LED

REF

I-PROT

IO-BDAT

BDA

DISPLAY

21

35

3

17

37

18

36

5

Screw +BVTP 4x16

Chassis Assembly

C Board

A Board

Screw +BVTP 4x16

2 Screws +BVTP 4x16

Claw

Rear Cover

1.  Discharge the anode of the CRT and remove the anode cap.

2.  Unplug all interconnecting leads from the defl ection yoke, neck 

assembly, degaussing coils and CRT grounding strap.

3.  Remove the C Board from the CRT.

4.  Remove the chassis assembly.

5.  Loosen the neck assembly fi xing screw and remove.

6.  Loosen the defl ection yoke fi xing screw and remove.

7.  Place the set with the CRT face down on a cushion and remove 

the degaussing coil holders.

8.  Remove the degaussing coils.

9.  Remove the CRT grounding strap and spring tension devices.

10. Unscrew the four CRT fi xing screws [located on each CRT 

corner] and remove the CRT  [Take care not to handle the CRT 
by the neck].

Coated
Earth
Ground
Strap

WARNING: High voltage remains in the CRT even after the power is disconnected. To avoid electric shock, discharge CRT before attempting to  
remove the anode cap.  Short between anode and coated earth ground strap of CRT. 
NOTE:  After removing the anode cap, short circuit the anode of the picture tube and the anode cap to either the metal chassis, CRT shield, or 
carbon painted on the CRT. 

1.  Do not use sharp objects which may cause damage to the surface of the anode 

cap. 

2.  To avoid damaging the anode cap, do not squeeze the rubber covering too hard. 

A material fi tting called a shatter-hook terminal is built into the rubber. 

3.  Do not force turn the foot of the rubber cover. This may cause the shatter-hook 

terminal to protrude and damage the rubber.

10

1

9

8

7

6

5

4

3

2

Turn up one side of the rubber cap in 
the direction indicated by arrow  a  .

1

Use your thumb to pull the rubber
cap fi rmly in the direction indicated
by arrow  b  .

2

When one side of the rubber cap separates from 
the anode button, the anode cap can be removed 
by turning the rubber cap and pulling it in the 
direction of arrow  c  .

3

The following adjustments should be made when a complete 
realignment is required or a new picture tube is installed. 

These adjustments should be performed with rated power supply 
voltage unless otherwise noted.

Set the controls as follows unless otherwise noted:
VIDEO MODE: Standard
PICTURE CONTROL: Normal
BRIGHTNESS CONTROL: Normal

Perform the adjustments in order as follows:
 

1. 

Beam Landing

 

2. 

Convergence

 

3. 

Focus

 

4. 

Screen (G2)

 

5. 

White Balance

Note Test Equipment Required:
 

1. 

Color Bar Pattern Generator

 

2. 

Degausser

 

3. 

DC Power Supply

 

4. 

Digital Multimeter

Before beginning adjustment procedure:

1.  Degauss the entire screen.

2.  Feed in the white pattern signal.

1.  Input a raster signal with the pattern generator.

2.  Loosen the defl ection yoke mounting screw, and set the purity control 

to the center as shown below:

Purity Control

3.  Turn the raster signal of the pattern generator to green.

4.  Move the defl ection yoke backward, and adjust with the purity control 

so that green is in the center and red and blue are even on both 
sides. 

Blue

Red

Green

5.  Move the defl ection yoke forward, and adjust so that the entire screen 

becomes green. 

6.  Switch over the raster signal to red and blue and confi rm the 

condition.

7.  When the position of the defl ection yoke is determined, tighten it with 

the defl ection yoke mounting screw.

8.  If landing at the corner is not right, adjust by using the disk magnets. 

a

c

b

d

b

a

c

d

Purity control

corrects this area

Disk magnets

or rotatable disk

magnets correct

these areas (a-d)

Deflection yoke positioning

corrects these areas