RCA 55AN3D, Service Manual

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c) Check whether the backlight control signal (BKL_EN) of the 2th pin socket XS808 is
high level (beyond 3V) or not, if not, check whether the backlight control circuit is open or
short.
4.3.6 网络功能
a) 检查 TU01 供电电压 2.5V 是否正常。
b) 检查 TU01 周边电路有无虚焊，漏焊，短路。
4.3.6 Net function
a)Check TU01 power supply(2.5v)is normal or not
b)Check if peripheral circuit of TU01is open or short.
4.4
4.4 4.4
4.4
主板调试
4.4.1 阻抗测试
测试方法：万用表选择电阻档，测量主板的各个供电端是否对地短路
4.4 Adjust mainboard
4.4.1Test method
：
Use a multimeter to measure every power supply points on the main
board to find whether they are short to ground.
序号
serial
number
项目
Project
测试点
Test point
标准
Standard
1 12V输出端电阻
The resistance of 12V
output on the main board
F801,L802,L805,L810,L201 无短路
no short
2 5Vstb输出端电阻
The resistance of 5V
output on the main board
L804，L808,L816,L807 无短路
no short
3 3.3V输出端电阻
The resistance of 3.3V
output on the main board
C845,L815,L814,R502,L504
,CU04
无短路
no short
4 1.23V输出端电阻
The resistance of 1.23V
output on the main board
C814 无短路
no short
5 1.5V端输出电阻
The resistance of 1.5V
output on the main board
C869,C430,C456 无短路
no short
6 5VA输出电阻
The resistance of 5V
C856 无短路
no short