Display Provided When Self-Diagnostic Function Started - Yamaha RX-V1800 Service Manual

• Display provided when Self-Diagnostic
Function started
The FL display of the main unit displays the protection
function history data and the version (1 alphabet) then the
main menu (sub-menu
THROUGH) a few seconds later.
When there is no history of protection function:
Opening message /
When there is no protection history
DIAGNOSTIC
When there is a history of protection function:
When there is a history of protection function due
to excess current
Cause: An excessive current flowed through the power
amplifier.
Suppleementary information: As current of the power
transistor is detected, the abnormal channel can be
identified by checking the current detect transistor.
Turning on the power without correcting the abnormality
will cause the protection function to work immediately and
the power supply will instantly be shut off.
Note)
• Applying the power to the main unit without cor-
recting the abnormality can be dangerous and
cause additional circuit damage. To avoid this, if
protection function has been activated 3 times
continuously, the power will not turn on even
when the "MASTER ON/OFF" key is pressed. In
order to turn on the power again, disconnect the
power cable of the main unit from the AC outlet
once and then reconnect it again.
• The output transistors in each amplifier channel
should be checked for damage before applying
power of the main unit.
• Amplifier current should be monitored by measur-
ing DC voltage across the emitter resistors for
each channel.
of main menu No. 1 DSP
After a few seconds /
When there is a history of protection
function due to excess current
DIAGNOSTIC
I PROTECT
RX-V1800/HTR-6190/DSP-AX1800
Main menu display /
1.DSP THROUGH
MARGIN
37