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Short circuit the anode of the picture tube and the anode cap to the metal chassis, CRT shield, or carbon painted on the CRT, after 

removing the anode.

An isolation transformer should be used during any service to avoid possible shock hazard, because of live chassis. The chassis of this 

receiver is directly connected to the AC power line.

Components identified by shading and 

 mark on the schematic diagrams, exploded views, and in the parts list are critical for safe 

operation. Replace these components with Sony parts whose part numbers appear as shown in this manual or in supplements published 

by Sony.  Circuit adjustments that are critical for safe operation are identified in this manual. Follow these procedures whenever critical 

components are replaced or improper operation is suspected. 

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 specified 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.

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).

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).

To Exposed Metal 

Parts on Set

0.15 µF

1.5 K Ω

AC

Voltmeter

(0.75 V)

Earth Ground

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.

 

*One flash count is not used for self-diagnostic.

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

is displayed on the screen.

**Refer to Screen (G2) Adjustments in Section 2-4. of this manual.

Standby indicator

Turn off the power switch on the TV main unit or unplug the power cord from the outlet to stop the STANDBY LED Indicator from flashing.

For errors with symptoms such as “power sometimes shuts off” or “screen sometimes goes out” that cannot be confirmed, it is possible to bring up past 

occurrences of failure on the screen for confirmation.

The units in this manual contain a self-diagnostic function. If an error occurs, the STANDBY LED indicator 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 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 LED indicator will flash a set 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.

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 

+B overcurrent (OCP)* 

V-Protect (OVP)

IK (AKB)

Does not light

2 times *

4 times

5 times

2:0 

or 

2:1 - 255

4:0 

or

 4:1 - 255

5:0 

or 

5:1 - 255

•  Power cord is not plugged in.
•  Fuse is burned out (F600). (A Board)

•  H.OUT (Q805) is shorted. (A Board)
•  IC751 is shorted. (C Board)

•  +13V is not supplied. (A Board)
•  IC804 is faulty. (A Board)

•  Video OUT (IC1545) is faulty(A Board)
•  IC001 is faulty.  (A Board)
•  Screen (G2) is improperly adjusted.**

•  Power does not come on.
•  No power is supplied to the TV.
•  AC Power supply is faulty.

•  Power does not come 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.

Power Supply
NG (+5V) for
Video Processor

8 times

8:0 

or 

8:1 - 255

•  IC604 is faulty.
•  IC602 is faulty.

•  No power supply to CRT Anode.
•  No RASTER is generated.

In standby mode, press buttons on the Remote Commander sequentially, in rapid succession, as shown below:

 

DISPLAY

  

 Channel  5      

 Sound Volume  -  

 

 POWER

 

 

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

 

Number “0” means that no fault was detected.

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

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 displ�

To clear the re�

Channel  8 

  0

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

A BOARD

IC001

Y/CHROMA JUNGLE

A BOARD

IC804

V. OUT

A BOARD

IC001

SYSTEM

A BOARD

IC003

MEMORY

IK

FROM

C BOARD

IC751 PIN 5

EHTO

FROM

A BOARD

Q816

COLLECTOR

32

RED-LED

F.B-PLS

V. GUARD

SDAO

SDA

DISPLAY

84

3

13

122

5

109

Occurs when an overcurrent on the +B (135V) line is detected by pin 32 of IC001 (A Board). If the voltage of pin 32 of IC001 (A Board) is more than 4V 

when V.SYNC is more than seven verticals in a period, the unit will automatically turn off. 

Occurs when an absence of the vertical deflection pulse is detected by pin 13 of IC001 (A Board). Power supply will shut down when waveform interval 

exceeds 2 seconds. 

If the RGB levels* do not balance within 15 seconds after the power is turned on, this error will be detected by IC001 (A Board). TV will stay on, but there 

will be no picture.

Occurs when IC001 internal HV protect detects an abnormal H-Pulse (frequency) due to improper power supply to IC001. The TV cuts off high voltage 

power of anode CRT. No picture will be detected. eg: faulty IC602 or IC604