KV-HS29M90 (serv.man2) - Sony TV Service Manual (repair manual). Page 7

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[+B overcurrent ªOCPº]

Occurs when an overcurrent on the +B(135) line is detected by Q5004(D board). If
Q6610(D board) go to ON,  the voltage to pin 5 of IC001(A board) go to UP. The unit
will automatically turn off.

[+B overvoltage ªOVPº]

Occurs when an overdrive on the +B(135V) line is detected by D6635(D board), Q6611
and Q6619. If Q6611 go to ON, the voltage to pin 8 of IC001 go to UP. The unit will
automatically turn off.

[Vertical deflection failure]

Occurs when an absence of the vertical deflection pulse is detected by Q5010. Shut
down the power supply.

[White balance failure]

If the RGB levels do not balance or become low level within 5 seconds. This error will
be detected by IC4300. TV will stay on, but there will be no picture.

[High voltage undervoltage protection ªHV UVPº]

High-voltage undervoltage conditions may indicate defective transformer, rectifiers,
CRT or fault within the power supply circuit. When high-voltage drops for any reason,
so does the voltage at T8001.17 and buffer IC8004.7. The malfunction is detected by
comparator IC8006A that generates high logic signal labeled H PROT. This signal is
sent via D8014 to the H prot that opens contacts of the AC relay RY6501 and turns off
main power.

[Audio Protector ]

If the Audio out line became DC. This error will be detected by Q1211, Q1209, and
Q1210.The unit will automatically turn off.

IC4300

CXA2170Q

RGB JUNGLE

FROM

CRT(IK)

Q5018, D8035 
(D Board)

IC001

SYSTEM

IC003

MEMORY

IO-SDAT

IK-IN

HPROT

SDA1

LED

SDA0

5

15

24

57

22

46

52

Q5010 
(D Board)

V PROT

56

OCP

V PROT

5

OVP

V PROT

8

H PROT 87

IC2602
( A Board)

Au PROT

100

IC1203,1240

(A Board)