Bang & Olufsen BeoLab 9 6217, Service Manual

Page: 11 / 40

Fault flow chart 2.5
Fault symtom:
- No sound from midrange, but tweeter and
woofer is OK
Possible cause:
- Midrange
- 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 midrange input
terminals.
Note:
It wil give the best result if it is possible to
use a audio test CD with pure sine waves
and an oscilloscope, when measuring on
the woofer or midrange
Visual confirm cable
connection between
midrange and Module
999, Amplifier
Reconnect/replace
cable
Remove mains from the
product. Remove the black
wire from the midrange.
Measure the resistance across
the midrange terminals:
Approx 6. ohm?
Replace midrange
Replace Module 999,
Amplifier
Fault symtom:
- No sound from tweeter, but midrange and
woofer is OK
Possible cause:
- Tweeter
- 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 between PCB, Cross Over
P0 pin and ground.
Visual confirm cable
connection between
tweeter and Module
999, Amplifier
Reconnect/replace
cable
Remove mains from the
product. Remove the connector
on PCB, Cross Over P0.
Measure the resistance
between the orange and white
wire:
Approx 6.6 ohm?
No
Yes
Replace tweeter
Replace Module 999,
Amplifier