Fault Flow Chart; No Function And No Led Indication - Bang & Olufsen BeoLab 18 Service Manual

2.6

Fault flow chart

Fault flow chart
Fault symptom:

No function and no LED indication

Possible causes:
Defective PCB04, Power Supply
Defective PCB30, Digital Sound Engine
Defective PCB35, Amplifier
Incorrect role switch setting
Confirm that the
role switch setting
is correct
OK?
Confirm that the
wireless connection
between the speaker
and the transmitter
is OK
OK?
Confirm 5V_SB at
PCB04, P3 pin 6
OK?
Confirm 3V at
PCB04, P3 pin 3
OK?
Confirm 28V at
PCB04, P4 pin 1,2
and -28V at PCB04,
P4 pin 7,8
OK?
Replace PCB35,
Amplifier
Use ServiceTool to
calibrate the new
module
Is the speaker in a
wireless setup
Set role switch
Repair/setup the
wireless connection
Disconnect cable
W4 from PCB04 P3
Confirm 5V_SB at
PCB04, P3 pin 6
Replace PCB30,
Digital Sound Replace PCB30,
Engine Digital Sound
OK?
Disconnect W4 from PCB35, P3.
Confirm 28V at PCB04, P4 pin 1,2
and -28V at PCB04, P4 pin 7,8
OK?
Confirm that the
role switch setting
is correct
OK?
Confirm that the
wired connection
between speaker
and the source
product is OK
OK?
Confirm mains
voltages at PCB04,
P1 pin 1-2
OK?
OK?
Replace PCB04,
Power Supply
Engine
Replace PCB04,
Power Supply
No
Yes
Set role switch
Repair/replace
connection
Fault in cable
connection
Repair/replace
connection
Replace PCB35,
Amplifier
Use ServiceTool to
calibrate the new
module
Survey of plugs and pins - see page 2.13