Philips BDP3080/98 Service Manual page 13

No display on VFD, and buttons do not work
No display on VFD, and
buttons do not work
Check
voltage on main board is
normal
Check-28V,5V,+12V
voltage on the power
and front board
Check the front board
signals SCK,SDA, STB
1.Check whether bad solder exists
on U3 and pins of VFD,
2.Check
connected to K1, K2, K3, K4, K5,
K6 is broken.
Replace U4 or VFD
Yes
every supply
Yes
Yes
Yes
whether the circuit
Yes
4-1
No
Refer to Power supply board part
No
Fix the connection JP1 on front board
and CN502 on power board
No Check the U4s pin 8,9,6 arrive the
condition JP2'3,4,5
No
Correct connection
Trouble shooting chart