Panasonic KX-FT72BR-G Service Manual page 67

2.3.8. POWER SUPPLY BOARD SECTION
1. Key components for troubleshooting
The following components have been known to break frequently:
F101, D101-D104, C106, Q101, PC101.
This comes from our experience with experimental tests. For example: power supply,
lightning surge voltage test, withstanding voltage test, intentional short circuit test, etc.
Caution:
If you find a melted fuse in the unit, don't turn the power on without repairing the unit first. (Except for the fuse.)
If you do, the fuse will melt again and the unit has not been repaired. The problem exists somewhere else.
In most cases, (our experience) the symptom is that nothing is output.
There is a high possibility in the primary side more than the secondary side.
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