Check Sheet - Panasonic KX-FM89BX Service Manual

Note:
{ }: Inside the digital board
[ ]: Inside the operation board
2.3.8.2. DEFECTIVE ITS (Integrated Telephone System) SECTION
1. No handset and speakerphone transmission / reception
Perform a signal test in the ITS or the NCU section and locate a
defective point (where the signal disappears) on each route
between the handset microphone and telephone line (sending), or
between the telephone line and the handset speaker (receiving),
or between the microphone and the telephone line (sending), or
between the telephone line and the speaker (receiving). Check the
components at that point.

CHECK SHEET

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