Toshiba SD-2815 - Μ-Com Circuit

3-3
Replace Main B/D
Refer to Front Part
Replace IC503
Reconnect it.
2. µ-COM Circuit
A. No Power
Does Logo appear
on the screen?
Is oscillation of
X501 normal?
Are IC501 Pins 193, 808
and 81 normal?
Do “Hello” appear at FLD?
Is P3901
connected normally?
Is P3901 Pin 7, 8, 9 normal?
The waveform
on 3, 5, 7 pin of IC503
normal?
Check the oscillation
Check short.
OK
Replace IC501
or IC3F1.
Check power.
(Refer to power)
If power is
normal
OK
POWER ON
1
1
YES
YES
YES
NO
YES
YES
YES
A
NO
NO
NO
NO
NO
NONO
YES
A