Μ-Com Circuit - NAD T572C Service Manual

2. µ-COM Circuit
A. No Power
Does Logo appear
on the screen?
YES
OK
1
Is oscillation of
X501 normal?
YES
Are IC501 Pins 193, 80
and 81 normal?
YES
A
POWER ON
YES
Does "Hello" appear on FLD?
NO
NO
Check the oscillation
NO
Check short.
OK
Replace IC501
or IC3F1.
NO
Is P3901
NO
connected normally?
Reconnect it.
Refer to Front Part
Replace IC503
3-3
YES
Check power.
(Refer to power)
If power is
normal
YES
Is P3901 Pin 15,
16, 19 normal?
NO
A
NO NO The waveform
on 3, 5, 7 pin of IC503
normal?
YES
Replace Main B/D
1