26
8. Protection Block (HA-3 Chassis)
8/30/01
25TVP12
The following test for the video output ICs is
quick, but dangerous to the technician. In the
next box, you will unplug the TV, then unplug
the C board from the CRT.
You must keep
away from the CRT pins, especially at TV
turn ON and OFF. The exposed CRT pins
will have 37kV on them in this test. Plug
the C board back only when the TV is OFF.
With the TV OFF, unplug the C
board from the CRT. Also unplug
the 200V supply to this board by
removing CN9002. Insulate the
board, keep away from the CRT
pins and turn ON the TV. Does
the TV stay ON?
TV SHUTS OFF WITHIN 6 SECONDS OF POWER ON
NO STANDBY LED DIAGNOSTIC INDICATION
Remove the fusible R8051
(D Bd) to stop B+ to HV
converter stage. Turn ON
the TV. Does the TV stay
ON?
Check Video Output
IC9001-3 (C Bd) for
shorts and Y/C CRT
Drive IC3101 for
constant 9V high at R,
G, or B output (A Bd)
Problem is in the
HV converter
stage (D Bd.)
Go to
Flow Chart B
No
No
Yes
Yes
D Board
Q8009
FBT
R8051
Front of TV
CN6503
CN6505
CN6504
CN6506
CN6503
CN6505
CN6501
1
8
10
1
Pin 1 of each connector
begins at this end.
PH6503/pin 3
The problem is in the:
Primary PS (A Bd),
Surge Relay circuit ( D Bd.), or
Latch circuit (D Bd.)
FIGURE 8-4 - FLOW CHART A
TV SHUTS OFF WITHIN 6 SECONDS OF POWER ON
NO STANDBY LED DIAGNOSTIC INDICATION
PRESS
POWER ON
BUTTON
7VDC AT
CN4403/2-(A BD.)
(CN6503/2-D BD.)
NO
TROUBLESHOOT A BD.'s
PRIMARY POWER SUPPLY
(IC6001)
YES (MOMENTARY)
200V AT
Q8009/BASE & EMITTER
(D BD.)AFTER
PRESSING POWER ON?
LESS THAN 3VDC
AT PH6503/PIN 3
(D BD.) AT POWER ON
NO
NO
REPLACE
SURGE
RELAY
RY6502
AND
PH6503 (D BD.)
LESS THAN 0.3V AT
Q8009/C
(D BD.) AT POWER ON?
YES
HV
CONVERTER
IS DEFECTIVE
(D BD.)
LATCH Q6503
Q6526,Q6528-9
ARE
SUSPECT (D BD.)
ABNORMAL FBT
ABL VOLTAGE
CHECK FOR
SHORTED VIDEO
OUTPUT IC's OR
SHORTED FBT,
EXCESS HV
YES
MORE THAN 5VDC
(ABL VOLTAGE)
AT FBT T8001/PIN 1
AT POWER ON?
LATCH CIRCUIT DEFECT
AT Q6530,Q6532 (D BD.)
YES (MOMENTARY)
NO
YES
NO
9/4/01
22TVP12 1340
FIGURE 8-5 - FLOW CHART B
Summary of Contents for KD-34XBR2 - 34" Hdtv Fd Trinitron Wega
Page 77: ...74 RA 5A Chassis Board Layout ...
Page 108: ...APPENDIX ...