The Power Cannot Be Turned On - Marantz PM-12 SE Service Manual

TROUBLE SHOOTING

1. The power cannot be turned on

(The standby LED does not light (standby mode))
INDUCTOR PCB
Check insertion of the connector.
OK
POWER PCB
Check insertion of the connector.
OK
Check the conduction of the SUB TRANS [T8501]
winding
No conduction.
Broken wire in SUB TRANS Malfunction of [D8501, D8502,
[T8501]. D8503, D8504].
It conducts.
Check the conduction of [D8501, D8502, D8503,
D8504].
No conduction. It conducts.
Malfunction of [D8507 or
U8501].
2. The power cannot be turned on
Check insertion of each connector.
OK
POWER PCB
Is the voltage of +12V output to [N8501 : 7pin]?
NG
Malfunction of the power supply circuit between [N8601] and [U8701] in the POWER PCB.
Check for short circuits or wire breaking of the parts.
45
(STANDBY LED is lit → light flashes)
OK
Check the applicable circuit according to
Protection operation".
If there are no issues, there is a malfunction in
the M_B_DOWN detection circuit of the UCOM
PCB.
"3.