No Sound From Midrange, But Tweeter And Woofer Is Ok; No Sound From Tweeter, But Midrange And Woofer Is Ok - Bang & Olufsen BeoLab 9 6217 Service Manual

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.
Remove mains from the
product. Remove the black
wire from the midrange.
Measure the resistance across
the midrange terminals:
Approx 6. ohm?
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.
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?
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
midrange and Module
Replace Module 999,
Replace midrange
Replace Module 999,
Replace tweeter
Visual confirm cable
connection between
Reconnect/replace
999, Amplifier
Amplifier
Visual confirm cable
connection between
Reconnect/replace
tweeter and Module
999, Amplifier
Amplifier
Fault flow chart 2.5
No
Yes
cable
cable