Service manual

2. TROUBLESHOOTING
2.4 Service Manual BSM-4100
Sound Problems
Key Operation Problems
Problem Possible Cause/Criteria Action
Faulty connection between CN006 on the
MAIN board and the speaker.
Check the connection.
Faulty speaker. Replace the speaker.
No sound.
Faulty MAIN board. Replace the MAIN board.
Faulty MAIN board. Replace the MAIN board.
No sound, except for a
hissing sound.
Faulty speaker. Replace the speaker.
The speaker is blocked. Remove the object blocking the speaker.
Something foreign is touching the speaker. Remove the foreign matter.
The sound is muffled or
distorted.
The speaker is wrongly attached. Attach the speaker correctly.
Problem Possible Cause/Criteria Action
Faulty connection between CN102 on the
Operation board and CN103 on the MAIN
board.
Check the connection.
Faulty MAIN board. Replace the MAIN board.
No key on the front panel
works.
Faulty Operation board. Replace the Operation board.
Faulty connection cable between CN102 on the
Operation board and CN103 on the MAIN
board.
Replace the connection cable.
Faulty Operation board.
Replace the Operation board.
A specified key on the
operation panel does not
work.
Faulty MAIN board.
Replace the MAIN board.
Incorrect calibration of the touch screen.
Calibrate the touch screen positioning.
Faulty connection between the touch screen
and Connection board.
Check the connection.
The workable key area
does not match the key
display on the screen.
Faulty connection between connection board
and MAIN board.
Check the connection.
Faulty connection
between the touch
screen and CN102 on
the Connection board.
Check the connection.
Faulty MAIN board.
Replace the MAIN board.
The key function on
the entire screen does
not work.
Faulty touch screen.
Replace the touch screen.
Touch screen does not
work.
The key function on a
partial screen such as
upper half screen does
not work
Faulty touch screen. Replace the touch screen.
Faulty connection between the Operation board
and Function Dial board.
Check the connection.
Faulty Function Dial board. Replace the Function Dial board.
Function dials are not
operational.
Faulty MAIN board. Replace the MAIN board.