Philips HTS3582/93 Service Manual page 39

VFD No display on Front Control Board
VFD No display on
Front Control Board
Go
Check every supply voltage on Main Board
whether normal or not.
(XP8 PIN4:-24V, PIN6: +5V, PIN5: 12V)
Yes
Check voltage -24V, +5V,+12V on Power
Board at CN502 position and Front Control
Board at XP2 PIN11:-24V
PIN9:+5V
Yes
Check the power key S608, open/closed key
K138, source key K135, paly/pause key
K136 on Front Board whether work normally
or not
Yes
Check Front Control Board signals at XP2
Pin8 VSCLK, Pin7 VSDA,Pin6 VSTB
Yes
Check whether bad solder exists on XP2 on
Front Control Board and U135 of VFD
Yes
Replace U135 or VFD
5-1
No
Refer to XP501 on Power Board
No
Fix the connection XP2 on Front
Control Board and XP8 on Main Board
PIN10:+12V
No
Replace MCU U4 on Main Board, or
replace the Main Board
No
Check the XP2 ON Front Control Board Pin6,
7, 8 arrive the condition IC U135 PIN7,9,10
No
Correct connection
Trouble shooting Chart