No Sound Output From Internal Speakers - Bang & Olufsen BeoPlay V1-40 MKII Service Manual

3.10 Fault flow chart
Fault symptom:
No sound output from internal
speakers
Possible causes:
PCB04, Power Supply
PCB35, ICEpower Amplifier
PCB01, Video Engine
Speaker box (incl. NTC)
Speaker units
Is sound missing in
See
Right/Woofer
page
speakers.
3.12
* and #
Check cables
Confirm voltages:
on PCB35
(right/woofer), P1
(right/woofer), P1
and PCB04, P4
pin 4+5 = +12V
pin 6+7 = GND
pin 8+9 = -12V
or similar testpoints
on PCB04, P4
pin 1+2 = +12V
pin 3+4 = GND
pin 5+6 = -12V
All OK?
Check cable
between Replace cable or
PCB01, P131 and re-establish
PCB35, P1
(right/woofer)
OK?
Warning:
Be very careful when measuring on the output to a loudspeaker, as there is
approx. 35 VDC on both terminals.
Make sure to use a differential probe, or that the oscilloscope and the product
are not connected to earth/ground.
Check cables and
connectors
between both
PCB35, P2 and
speaker box
OK?
Confirm voltage on
PCB01, P142, pin 1
SPK_NTC_IN4
= 2.7V±0.3V
OK?
between Replace cable or
PCB35 re-establish
connection
Sound OK?
OK?
Disconnect cable from PCB35, P1.
Confirm voltages on: PCB04, P4
pin 1+2 = +12V
pin 3+4 = GND
pin 5+6 = -12V
OK?
Confirm voltage:
DSE_OUTPUT3_N
on PCB01, P131
connection
pin 7 = +12V
OK?
PCB01, P131 pin 1 SPK_IN_3P approx. = +5V
PCB01, P131 pin 4 SPK_IN_4P approx. = +5V
Replace PCB35,
ICEpower Amplifier
right/woofer
Sound OK?
Replace the
Speaker box
(incl. NTC)
Replace PCB04,
Power Supply Unit
Disconnect cable
from PCB01, P131.
Confirm voltage on
PCB35 P1 pin 3
Monitor out ch1/
Disable = 12V
OK?
Confirm voltage on
(tweeter) and
(left woofer)
OK?
Yes
Press
MENU > SETUP > SOUND >
SPEAKER GROUPS >
SPEAKER GROUP SETUP >
TV > SPEAKER ROLES to
check sound in speakers
The ServiceTool provides test
sounds to the individual
loudspeakers of the TV
Replace the failing
Replace PCB35,
right speaker/
ICEpower Amplifier.
Sound OK?
Replace PCB01,
Video Engine
** Acceptable ohmic
speaker values:
plugs, pins and test
Full range: 3.6 Ω ±0.5Ω
Woofer: 6.4 Ω ±1Ω
No
*
#
woofer
**
Hint:
Measurement
points;
see page 3.17