Philips HTS3564, Service Manual

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5-1 Trouble shooting Chart
VFD No display on Front Control Board
V F D No display on
F ront Control Board
Go
Yes
R efer to XP501 on Power Board
No
F ix the connection XP2 on F ront
Control Board and XP8 on Main Board
No
R eplace MCU U4 on Main Board, or
replace the Main Board
No
Check the XP2 ON F ront Control Board Pin6,
7, 8 arrive the condition IC U135 PIN7, 9 ,10
No
Yes
Yes
Yes
Correct connection
No
Yes
R eplace U135 or V F D
Check every supply voltage on Main Board
whether normal or not.
(XP8 PIN4 : -24V, PIN6 : +5V, PIN5 : 12V)
Check voltage -24V, +5V,+12V on Power
Board at CN502 position and F ront Control
Board at XP2 PIN11 : -24V PIN10 : +12V
PIN 9: +5V
Check the power key S608, open/closed key
K138, source key K135, paly/pause key
K136 on F ront Board whether work normally
or not
Check F ront Control Board signals at XP2
Pin8 VSC L K, Pin7 VSDA,Pin6 VSTB
Check whether bad solder exists on XP2 on
F ront Control Board and U135 of V F D
Yes