Sony A1E Series Service Manual page 43

FLOW
5. KEY SWITCH BUTTONS ERROR
Resistor value
[BKA]
R260 : 0 [ohm]
R258 : 47k [ohm]
R1222 : 4.7k [ohm]
Resistor value
[BKA]
R1028 : 4.7k [ohm]
R259 : 0 [ohm]
R256 : 20k [ohm]
R257 : 22k [ohm]
XBR-55/65/77A1E
Side key buttons error
OK
Check harness connection
between
BKA board and switch module
NG
OK
Change harness between
BKA board to switch module
harness
NG
OK
Change switch module
NG
NG
Check resistor value on BKA
board
OK
In case that power key error
NG
Check resistor value on BKA
board
In case that buttons error except power key
OK
TROUBLE SHOOTING
Harness connection issue
BKA board to switch module harness
issue
Switch module issue
Parts issue
Main device issue
Change BKA board
43