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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 identifi ed 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 identifi ed in this manual. Follow these procedures 
whenever critical components are replaced or improper operation is suspected. 

Apres avoir deconnecte le cap de l’anode, court-circuiter l’anode du tube cathodique et celui de l’anode du cap au chassis metallique 
de l’appareil, ou la couche de carbone peinte sur le tube cathodique ou au blindage du tube cathodique.

Afi n d’eviter tout risque d’electrocution provenant d’un chássis sous tension, un transformateur d’isolement doit etre utilisé lors de tout 
dépannage. Le chássis de ce récepteur est directement raccordé à l’alimentation du secteur.

! 

Les composants identifi es par une trame et par une marque ! sur les schemas de principe, les vues explosees et les listes de pieces 
sont d’une importance critique pour la securite du fonctionnement. Ne les remplacer que par des composants Sony dont le numero 
de piece est indique dans le present manuel ou dans des supplements publies par Sony. Les reglages de circuit dont l’importance 
est critique pour la securite du fonctionnement sont identifi es dans le present manuel. Suivre ces procedures lors de chaque 
remplacement de composants critiques, ou lorsqu’un mauvais fonctionnement suspecte.

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).

To Exposed Metal
 Parts on Set

AC Voltmeter
(0.75 V)

Earth Ground

0.15 

µ

F

1.5 

k

Ω

g

AC Outlet Box

Ohmmeter

Cold-water Pipe

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

Figure B. Checking for earth ground.

Diagnostic items 

Flash count

+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

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

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”, an error has occurred.

Power does not turn on  

Does not light 

_______ 

•  Power cord is not plugged in. 
•  Fuse is burned out (F501). (AZ 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 (Q5030) is shorted. (DZ Board) 
•  +B PWM (Q5003) is shorted.  

(DZ Board) 

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

Low +B Overvoltage (OVP) 

3 times 

3:0 or 3:1 

•  IC6505 is faulty. (DZ Board)  

•  Has entered standby mode. 

Vertical Deflection Stopped 

4 times 

4:0 or 4:1 

•  15V is not supplied. (DZ Board) 
•  IC5004 is faulty. (DZ 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 (IC9001-IC9003) is faulty. 

(CX Board) 

•  CRT drive (IC2801) is faulty.  

(BY 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.  

(AZ, BY, MZ Boards) 

•  +5 line is shorted.  

(AZ, BY, MZ Boards.)  

•  IC504 is faulty. (AZ Board) 

• No picture 

Horizontal Deflection 
Stopped 

7 times 

7:0 or 7:1 

 

• 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) in Section 2-5 of this manual. 
*** If STANDBY/STEREO LED flashes six (6) times, unplug the unit and wait 10 seconds before performing the adjustment. 

* One fl ash count is not used for 
   self-diagnostic.

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.

 

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:
NOTE: This will also reset all user functions (including auto programming and picture settings)

 

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.

Numeral “0” 

means that no fault was detected.

Numeral “1” 

means a fault was detected one 
time only.

1

2

4

3

3

1

2

R5104

R5105

R5125

Q5018

RY6501

Q6527

Q6530

Q6532

D6537

D6505

D5007

PH6501

Q5004

R5013

D5005

IC6505

Q6522

1K-PROT2

+B OVP

HV PROT

UNREG 11V

5V

UNREG 7V

+B OCP

2

1

3

4

IC5007

VDY-

CRT

IC2801

Y/C JUNGLE

SCL

SDA

AKB

VPROT

HPROT

IC2300

MAIN MICRO

BY

CLKO

DATO

AC RLY

LOW B ERR

OVP

OCP

STR
STBY-LED

STBY-LED

P_SW(-)

IC504

5V

+B

+B

+B

DZ

BY

MZ

DZ

DZ

AZ

2

14

34

35

58

26

25

29

30

69

43

44

45

48

O

I

O

☛