System Error; Power Pwb - Marantz MM7055/N1B Service Manual

3. SYSTEM ERROR

The reason for the error can be presumed from Standby LED display when the error occurs and protection log display.
Refer to [1-1.] for the method of confi rming protection log.
If the AC power supply is turned off, the state of all protection can be released.
Protection log
Error Detection
V1
D407
ON
Standby LED Blinking
125msec interval
(Fast Blinking)
OFF
ON
Standby LED Blinking
500msec interval
(Slow Blinking) OFF
ON
OFF
display
V2 V3
D406 D405
Detection of abnormality on +/-38V, +/-
15V supply or power amp supply
(_P LINE FAIL)
OFF ON
CPU (IC402) 45pin _P LINE FAIL :
0V : Fail
There is a possibility that ± 38 V supply or
P-AMP power supply is broken.
Detection of over current over 200msec
on Power AMP
(_P CUR FAIL)
OFF ON
CPU (IC402) 38pin _P CUR FAIL :
0V : Fail 5V : Normality
There is a possibility that Power AMP is
broken.
Detection of over current below 200msec
on Power Amp
(_P CUR FAIL)
OFF OFF
CPU (IC402) 38pin _P CUR FAIL :
0V : Fail 5V : Normality
Detection of DC on Power Amp output
(_P AMP FAIL)
ON OFF
Main-CPU (IC402) 41pin _P AMP FAIL :
0V : Fail 5V : Normality
Detection of abnormal heat of Power Amp
(_HEAT DET P)
ON OFF
Main-CPU (IC402) 24pin
0V : Fail 5V : Normality
OFF OFF No protection log
Reason
5V : Normality
15
Check Point
POWER PWB : BN12- 4pin
Connection
CPU PWB : CN41 - 4pin

POWER PWB :

Power Amp
IC13,IC14,D109,RY14,RY15
Supply Power
,F101,F102,D110-D113
AMP PWB : CN95 - 4pin,
CN94-8pin
Connection
CPU PWB :BN41 - 8pin.
Check Power AMP circuit
Power Amp
(AMP PWB)
AMP PWB : CN95 - 4pin,
CN94-8pin
Connection
CPU PWB :BN41 - 8pin.
Check Power AMP circuit
Power Amp
(AMP PWB)
AMP PWB :CN95 - 5pin,
Connection CN94-9pin
CPU PWB : BN41 - 9pin
Check Power AMP circuit
Power Amp
(AMP PWB)
AMP PWB : CN94 - 10pin
Connection
CPU PWB : BN41 - 10pin
Posistor TH91,TH92