Philips HTB3560/12, Service Manual

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5-1 Trouble shooting Chart
VFD No display on Front Control Board
VFD No display on
Front Control Board
Go
Yes
Refer to XP501 on Power Board
No
Fix the connection XP3 on Front
Control Board and XP9 on Main Board
No
Replace MCU U8 on Main Board, or
replace the Main Board
No
Check the XP3 ON Front Control Board Pin6,
7, 8 arrive the condition IC U301 PIN2,3,4
No
Yes
Yes
Yes
Correct connection
No
Yes
Replace U301 or VFD
Check every supply voltage on Main Board
whether normal or not.
(XP9, PIN6: +5V, PIN5: 12V)
Check voltage +5V,+12V on Power
Board at CN502 position and Front Control
Board at XP3 PIN10:+12V PIN9:+5V
Check the power key S608, open/closed key
S611, source key S609, paly/pause key
S610 on Front Board whether work normally
or not
Check Front Control Board signals at XP3
Pin8 VSCLK, Pin7 VSDA,Pin6 VSTB
Check whether bad solder exists on XP3 on
Front Control Board and U301 of LED