RCA 55AN3D, Service Manual

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4.3.3 Verify the state of TV set
Set
“
ON/OFF
”
on the right side of the TV set to
“
ON
”
and verify the LED indicator’s
color . If the LED color is red, TV is in standby state. If the LED color is green, TV is in working
state.
4.3.4 检查供电电压是否正常
若待机指示灯未亮时，信号板的电源被开启， 由 N802 产生 3.3V 电压，N801 产生 1.2V
电压，N803 产生 3V3 电压，然后 N808 产生 1.5V， N805 产生 5V，然后 N806 产生 2.5V，N807
产生 1.2V，然后 N809 产生 3.3V，V801 产生 12V 电压，以给主板上各部分元件供电。接上电源
后先用万用表检查开机后几项输出电压是否正常。
4.3.4 Checking supply power
Before TV enter standby condition, and signal board power on.N802 output 3.3V,N801
output 1.2V, N803 output 3V3,N808 output 1.5V, N805 output 5V,N806 output 2.5V,N807
output 1.2V N809 output 3.3V, V801 output 12V, Use a multimeter to check above those
supply power is normal or not
4.3.5 信号板信号部分
4.3.5 signal board part
开机时序
The time sequence of power on
start order
Turn on the
power
Reset N501 and
initialize each IO
port
Turn on LED
TCON power
Turn on
backlight
Successful start
and LOGO
display
通电几十秒钟后，若黑屏（背光灯不亮），需先确认是否处于待机状态。如果还是黑屏：
a)、检查各电源网络电压是否正常。
b)、检查晶体振荡器 Z501(24MHz)是否起振、振荡频率是否正确。
c)、检查插线 XS809 的背光控制信号（BKLT_EN）有无高电平（3V 以上），若没有，检查前级
是否有虚焊或短路。
Electrify TV in several minutes, if it shows black screen (backlight is not turned on), please
press the standby button. If TV still shows black screen,
a)Check whether power supplies is normal or not.
b)Check whether the crystal oscillator Z501 (24Mhz) works or not, and the oscillation
frequency is normal or not.
电源上电
N501
复位并初
始化各
IO
口
液晶屏模组上电
打开背光灯
开机成功
显示
LOGO