No display on VFD, and buttons do not work
No
No
Yes
No display on VFD, and
buttons do not work
Check every supply
voltage on main board is
normal
Refer to Power supply board part
Check if the U2 is o n the front
board
Correct connection
Replace VF D
Yes
Yes
Yes
No
Check the front bo ard
signals SCLK,SDA, STB
(Pin 10
,
11
,
12of the XP1)
1: check th e reset circuit for
R60,C14,D1.
Trouble shooting chart
5-1
Harman Kardon
BDT 3/120V and BDT 30/240V Service Manual
Page 15 of 35