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Model No.:
-52 -
9-2. M
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Power Units Proble
m
Sol
v
ing
In stand-by condition,
Check pin 10of J5,
Whether got 5V
˛
Whether main board testing TP8point got 3.3V?
Normal booting
Whether power suppply and main
board is shortcircuit?
Whether power chip LDO(U3)
works?
power chip LDO(U6) works?
diode (D29) works?
power chip (U1) works?
After power on, check
whether pin 3/4 of J5got 5v,
pin 1 of J5 got 12v, testing
point TP7 got 2.5v, testing
point TP3 got 3.3v, testing
point TP5 got 1.8v, testing
point TP1 got 1.32v?
Y
N
OK
Check U9 power
network
N
Y
Y
N
Check external
power suppply
