Sony XBR-55X900H Service Manual page 20

2020/06/27 06:31:32 (GMT+09:00)
1.2 No Power u-com Failure
BM5 Board LCD Model
START
Check VDD
C442 Voltage.
Is the voltage >3.0V?
yes
Check TYPE_DET
CL408 or R451 Voltage.
Is the voltage 2.6±0.2V?
yes
Check OPWRSB
CL411 or R460 Voltage.
Is the voltage 0V?
yes
Check POWER_ON
CL419 or R470 Voltage.
Is the voltage >3.0V?
yes
SECTION 1
T R O U B L E S H O O T I N G
no
Check 3.3V_STBY Line (C1708, CN1700 #9pin)
no
Type Detection Circuit problem.
Check TYPE_DET Line (R445, R446).
no
SOC
Muffin 5 problem
IC1000 # AP17 OPWRSB
Try AC Off and On after few minutes.
no
If #pin10 keep Low, change IC401.
If #pin10 goes High few seconds and downs to Low,
Check 12.7V_MAIN Line (from G board).
SECTION 2
S E C T I O N 3
Is the voltage >2.6V?
Check DC_OFF_DET
CL414
Is the voltage >3.0V?
P-on u-com #pin12 (IC401)
CL413
Is the voltage >3.0V?
SECTION 3 SECTION 4
no
Check 12V_MON
R462 Voltage.
yes
no
or R465 Voltage.
yes
Check P_ON_#1
no
CL418 or
is >3.0V?
yes
no
Check PGOOD_1 1.3 No POWER - DDCON/LDO
or R456 Voltage.
Continue next page...
SECTION 5
Check 12.7V_MAIN Line
and 12.7V_AUDIO Line
(from G board).
Change IC401
Change IC401
Check 0.8V_M5_CORE
DDCON (IC804)
20
SECTION 6
SYS SET