Sony XBR-55X850D Service Manual page 36

FLOW
2-5. LED BLINKING 6X (BACKLIGHT ERROR)
Case: BM1 + DPS structure
6-times blinking
Check Voltage of
BL_ERR_DET
on 21pin of CN401
on DPS
Voltage < 1.85 V
Symptom
Improvement
Change
DPS
No
Improvement
Change 30P FFC
between DPS and BM1
No
Improvement
BM1 Board
XBR-55X850D/857D, 65X850D/855D/857D, 75X850D
Voltage ≥ 1.85 V
Check
harness/connection
G/LD* board to DPS Board
DPS Board
Symptom
Improvement
30P FFC
Harness /
Connection
broken
Change
harness
No
improvement
Harness /
LED driver or G board
Connection OK
 Change LD board or G board.
No
improvement
Change
Panel
No
Improvement
TROUBLE SHOOTING
Symptom
Improvement
Harness
Symptom
Improvement
LD board / G board
Symptom
Improvement
Panel
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