Panasonic KX-FC379CX Service Manual page 129

KX-FC379CX
7.7.7.2. Defective ITS (Integrated Telephone System) Section
1. No handset transmission / reception and no monitor 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(P.126) is useful for this investigation.
2. No pulse dialing
3. No ring tone (or No bell)
CROSS REFERENCE:
Check Sheet(P.126)
NCU SECTION(P.178)
4. No tone dialing
CROSS REFERENCE:
Check Sheet(P.126)
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