Sony KP-46WT520 / KP-51WS520 / KP-57WS520 (serv.man2) Service Manual ▷ View online
KP-46WT520/51WS520/57WS520
KP-46WT520/51WS520/57WS520
6
SAFETY CHECK-OUT
After correcting the original service problem, perform the following
safety checks before releasing the set to the customer:
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.
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.
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.
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.
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.
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.
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.
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.
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).
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.
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).
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.
To Exposed Metal
Parts on Set
Parts on Set
AC Voltmeter
(0.75 V)
(0.75 V)
Earth Ground
0.15
µ
F
1.5
k
Ω
KP-46WT520/51WS520/57WS520
KP-46WT520/51WS520/57WS520
7
SELF-DIAGNOSTIC FUNCTION
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.
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.
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.
Diagnostic Item
No. of times
STANDBY /
TIMER lamp
flashes
Display
Result
Probable Cause Location
Detected Symptoms
Power does not turn on
Does not light
_______
•
Power cord is not plugged in.
•
Fuse is burned out (F6000). (G 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 (Q5001) is shorted. (D Board)
•
+B PWM (Q5201) is shorted.
(D Board)
•
Power does not come on.
•
Load on power line shorted.
+B Overvoltage (OVP)
3 times
3:0 or 3:1
•
IC6503 is faulty. (D Board)
•
Has entered standby mode.
Vertical Deflection Stopped
4 times
4:0 or 4:1
•
15V is not supplied. (D Board)
•
IC5101 is faulty. (D 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)
(not balanced)
5 times
5:0 or 5:1
•
Video OUT (IC9101, IC9201, IC9301)
is faulty. (CR, CG, CB Board)
•
CRT drive (IC452) is faulty.
(A Board)
(A Board)
•
G2 is improperly adjusted.**
•
No raster is generated.
•
CRT cathode current detection
reference pulse output is small.
LOW +B OCP/OVP
(overcurrent/overvoltage)***
(overcurrent/overvoltage)***
6 times
6:0 or 6:1
•
+5 line is overloaded.
(A and BM Boards)
•
+5 line is shorted. (A and BM Boards)
•
IC303 is faulty. (A Board)
•
No picture
Horizontal Deflection
Stopped
Stopped
7 times
7:0 or 7:1
•
Q5006 is broken (D Board)
•
IC452 is faulty (A Board)
•
No picture
Audio Protection
8 times
8:0 or 8:1
•
+ or - 22V audio supply is not
present—Check PS600 & PS601
•
Audio AMP is damaged IC601 on
A Board
A Board
•
No picture
Zero Crossing Detector
9 times
9:0 or 9:1
•
D6116 or D6301 is open (G Board)
•
No picture
HV Protection
10 times
10:0 or
10:1
•
Q8014 or Q8013 have shorted replace
along with R8051 on D Board
•
IC8005 is damaged (D Board)
•
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) Adjustment (Fine Adjustments) in Section 2 of this manual.
*** If STANDBY/STEREO LED flashes six (6) times, unplug the unit and wait 10 seconds before performing the adjustment.
*** If STANDBY/STEREO LED flashes six (6) times, unplug the unit and wait 10 seconds before performing the adjustment.
Self Diagnosis
Supported model
KP-46WT520/51WS520/57WS520
KP-46WT520/51WS520/57WS520
8
Display of Standby/Timer LED Flash Count
STAND BY Indicator
TIMER Indicator
Diagnostic items
Flash count
Lamp OFF 3 sec.
Lamp ON 0.3 sec.
Lamp OFF 0.3 sec.
+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
Audio Protection
8 times
Zero Crossing Detector
9 times
HV Protection
10 times
Release of TIMER STAND BY 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.
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.
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.
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 + )
Numeral “0”
means that no fault was detected.
Numeral “1”
means a fault was detected one
time only.
time only.
SELF DIAGNOSIS
2:
+B
OCP
0
3:
+B
OVP
0
4:
VSTOP
0
5:
AKB
1
6:
LOWB
0
7:
H-STOP
0
8:
AUDIO
0
9:
ZCD
0
10:
HV
PROT
0
101:
WDT
24
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.
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.
Method of Clearing Results Display
1. Power off (Set to the stand by mode.)
2. Display
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.
When ending the self-diagnosis screen completely, turn the power switch OFF on the remote commander or the main unit.
KP-46WT520/51WS520/57WS520
KP-46WT520/51WS520/57WS520
9
Self-Diagnosis Function Operation
+B overcurrent (OCP)
Occurs when excessive current fl ows through R6812. The increase in voltage across Q6803 causes it to turn on which sends a high signal to the
micro.
Occurs when excessive current fl ows through R6812. The increase in voltage across Q6803 causes it to turn on which sends a high signal to the
micro.
+B overvoltage (OVP)
IC6801 detects +B OVP condition and turns on Q6802. This sends a high signal to the micro and also shuts down the AC relay.
IC6801 detects +B OVP condition and turns on Q6802. This sends a high signal to the micro and also shuts down the AC relay.
V-STOP
Occurs when an absence of the vertical defl ection pulse is detected by pin 56 of IC452 (A Board). Power supply will shut down when waveform interval
exceeds 2 seconds.
Occurs when an absence of the vertical defl ection pulse is detected by pin 56 of IC452 (A Board). 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 IC452 (A Board). TV will stay on, but
there will be no picture.
If the RGB levels* do not balance within 2 seconds after the power is turned on, this error will be detected by IC452 (A Board). 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
Occurs when set 5V is out.
Also check for : + 135V line shorted
Occurs when set 5V is out.
Also check for : + 135V line shorted
+ 135V line is going over 145V
Horizontal Defl ection Stopped
Occurs when either:
Occurs when either:
1) a +B overcurrent is detected (Q6803), or
2) IC452 (A Board) is damaged.
Self-Diagnosis Block Diagram
3
1
2
R5104
R5105
R5125
Q5018
RY6000
Q6102
Q451
Q452
D452
D6803
D6505
D453
R6812
D6805
R6803
IC6801
Q6802
1K-PROT2
+B OCP
+BVOP
5V
+B OCP
2
1
3
4
IC5007
VDY-
CRT
IC452
Y/C JUNGLE
SCL
SDA
AKB
VPROT
HPROT
IC702
MAIN MICRO
A
CLKO
DATO
AC RLY
LOW B ERR
OVP
OCP
STR
STBY-LED
STBY-LED
STBY-LED
P_SW(-)
IC303
5V
+B
+B
+B
BM
A
D
D
A
2
14
57
56
58
53
52
28
31
69
43
44
45
48
3
1
2
G
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