Yamaha TX-497 Owner's Manual page 21

■ General
Problem
This unit fails to turn
The power cord is not connected or the
on when POWER is plug is not completely inserted.
pressed.
This unit has been exposed to a strong
external electric shock (such as lightning
or strong static electricity).
A "humming" sound
Incorrect cable connections.
can be heard.
This unit does not The internal microcomputer has been
operate properly.
frozen by an external electric shock (such
as lightning or excessive static electricity)
or by a power supply with low voltage.
Cause
Connect the power cord firmly.
Disconnect the power cord, plug it back in after 30 seconds, then
use it normally.
Firmly connect the audio connection cord plugs. If the problem
persists, the cables may be defective.
Disconnect the AC power cord from the outlet and then plug it in
again after about 30 seconds.
TROUBLESHOOTING
Remedy
17