Panasonic KX-FP342CX Service Manual page 138

CIRCUIT OPERATION()
2. A FAX is received, but won't switch from TAM to FAX.
CROSS REFERENCE:
ANALOG BOARD SECTION()
TAM INTERFACE SECTION()
6.6.9. POWER SUPPLY BOARD SECTION
6.6.9.1. KEY COMPONENTS FOR TROUBLESHOOTING
Check the following parts first: F101, D101-D104, C106, Q101, PC101 and IC101.
This comes from our experience with experimental tests. For example: power supply and
lightning surge voltage test, withstanding voltage test, intentional short circuit test, etc.
Caution:
If you find a melted fuse in the unit, do not turn on the power until
you locate and repair the faulty parts (except for the fuse);
otherwise the fuse will melt again and you cannot pinpoint the faulty
point.
In most cases, the symptom is that nothing is output. It is more likely that the fault is in the
primary side rather than the secondary side. Check the primary side first.
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