Yamaha RX-V671 Service Manual page 31

● Canceling Self-Diagnostic Function
1. Before canceling self-diagnostic function, execute setting for "S3. FACTORY PRESET" menu. (Memory initialization
inhibited or Memory initialized).
*
In order to keep the user memory preserved, be sure to select PRESET INHIBIT (Memory initialization inhibited).
2. Press the "MAIN ZONE " key to turn off the power.
● Display provided when Self-Diagnostic Function started
The display is as described below depending on the situation the last time the power to this unit is turned off.
1. When the power is turned off by usual operation:
"NO PROTECT" is displayed. "A1-1. DSP MARGIN" menu is displayed in a few seconds.
Opening message
2. When the protection function worked to turn off the power:
The data of protection function which worked at the moment is displayed. Then "A1-1. DSP MARGIN" menu is displayed in
a few seconds.
Note: At that time if you reactivate the self-diagnostic function after turning off the power once by pressing the "MAIN
ZONE " key, "NO PROTECT" will be displayed because that situation is equal to "1. When the power is turned off
by usual operation:" described above.
However the protection function history is stored in a back-up IC with a backup. For details, refer to "P2
PROTECTION HISTORY" menu.
2-1. When there is a history of protection function due to excess current.
Cause: An excessive current flowed through the power amplifier.
Supplementary information: As current of the power amplifier 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.
Notes)
• Applying the power to this unit without correcting the abnormality can be dangerous and cause additional
circuit damage. To avoid this, if "I PROTECT" protection function works 1 time, the power will not turn on even
when the "MAIN ZONE
function.
• The output transistors in each amplifier channel should be checked for damage before applying power to this
unit.
• Amplifier current should be monitored by measuring DC voltage across the emitter resistors for each channel.
After a few seconds
" key is pressed. In order to turn on the power again, start up the self-diagnostic
RX-V671/HTR-6064/RX-A710
Main menu display
31