Bang & Olufsen BeoLab 9 6217, Руководство по обслуживанию

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2.4 Fault flow chart
Fault symptom:
- No sound, but green LED is OK
Possible causes:
- Module 999, Amplifier
Is there no sound, but the green LED is OK?
Go to box
further down
on page
Replace Module 999,
Amplifier
From above
No
Yes
Note:
It wil give the best result if it is possible to
use an audio test CD with pure sine waves
and an oscilloscope, when measuring on
the woofer or midrange.
Warning:
Be very careful, when measuring on the
woofer, because there is approx 35Vdc on
both input terminals. Make sure to use a
differential probe, or make sure that the
oscilloscope and the product is not
connected to earth.
Fault symptom:
- No sound from woofer, but tweeter and
midrange is OK
Possible cause:
- Woofer
- Module 999, Amplifier
Turn volume on the Audio Master up to 50.
Confirm an AC-Sound signal by means of the
Bar-graph on the multimeter or an oscilloscope,
when measuring across the woofer input
terminals.
From previous
page
Visual confirm cable
connection between
woofer and Module
999, Amplifier
Reconnect/replace
cable
Remove mains from the
product. Remove the black wire
from the woofer. Measure the
resistance across the woofer
terminals:
Approx 2.9 ohm?
Replace woofer
Replace Module 999,
Amplifier