Philips CED780/05, Руководство по обслуживанию

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Tate 2011-11-28
NO.
b. To check whether the strength of then input signal of the tuner is too weak.
c. To check the voltage of the 13 pin of the U8 of the tuner IC, should be +3V3.
d.To check the voltage of the cathode of the D14 of the TFT board,should be +10V0.
4
Radio
abnormal
a. To check the antenna of the AM/FM tuner.
d. To check the oscillation frequence of crystal X3 of the tuner IC,shuold be 32.768MHz
e.If the TFT move defective, to check the U13(6208 IC) and the U9~U11 of the photo reflective, to check whether there is any
abnormal of the rotation of the TFT mechanism.
3
NO audio
output
a. To check whether the volume knob is turn to the minimum position.
b. To check whether the unit is at MUTE mode, press SOURCE button and check whether it is effective of the input sound
source.
c. To check whether the connection of 8 PIN audio output wire of ISO connector is correct; wrong connection or short circuit
to the ground will caused the protection of the power amplifier( no voltage output).
e. To check the voltage of 22 PIN(MUTE) of power amplifier U12(47002 IC) , normally should be 4V0.
d . To check the circuit of power amplifier U12(LV47002 IC) and VOLUME U7(47048 IC).
c. To check the U3 of multiple voltage regulator IC,the 9 pin should be +12V0 the 10 pin should be +5V0 the 1 pin should
be +3V3 the 13 pin should be +8V5 the 14 pin should be +5V0.
e. To check the oscillation frequence of crystal X1 shuold be 16MHz .
d. To check the 7 pin voltage of the U2(MCU) should be +5V0.
b. To check whether there is any contamination and bad contact on the 24 Pin male/female connector on the panel and main
board.
a. To check whether the CN2(14pin) connector of the tail of the unit is connect well , Whether it is loose of the 15A fuse of the
Filter Box, or insert non in place.
Trouble shooting Trouble shooting Trouble shooting Trouble shooting
failure
phenomena
failure cause remark
Product Model CED780
Area All area
1
NO Power
2
7"TFT
abnormal
a.To check the connectors of the CON6 CON9 whether the socket of it is loose.
c.To check the voltage of the L2 of the TFT board,should be +5V0.
b.To Check the voltage of the 33 pin~36 pin of the CON2 ,should be +12V0
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