Philips DCC170/00 - DRP, SFC, DAIO Communication Fault Location

(2)
Locating
the
deÍective
division oÍ
DRP,
SFG and
DAIO
communication
(Data
and Control
Line:
..DRP/SFC/
DAIO NG')
"DRP
NG",
"SFC
NG"
and
"DAIO
NG"
are all
displayed.
Unsolder
pins
@ to @ of
Q501(DRP),
pins
@
to @
of
Q551
(SFC),
and
pins
@
to
@
of
QA01
(DAIO)
to
Íloat them
from
the circuit.
"NG"
appears w'ni'fË3$':j3#
DAro
when
Solder
pins
@
to
@
of Q5o1(DRP).
Select DRP
Communication
Test
mode
in Service
mode
(see "How
To Enter
Service
Mode" on
page
19).
DRP
(Q501)
or its
peripheral
logic
is
defective.
"DRP
NG"
displayed?
"DRP
OK" displayed?
Solder
pins
@
to
@
of
Q551
(SFC).
Select SFC Communication
Test
mode
in Service
mode
(see
"How
To Enter Service
Mode" on
page
19).
SFC
(0551)
or its
peripheral
logic is
defective.
''SFC
OK" displayed?
"SFC
NG'displayed?
Solder
pins
@
to
@ of
QAol
(DAIO).
Select
DAIO
Communication
Test mode
in
Service
mode
(see
"How
To Enter
Service
Mode" on
page
19).
DAIO
(OA01)
or
its
peripheral
logic is defective.
"DAIO
OK"
displayed?
"DAIO
NG"
displayed?
The data
and control
lines
connecting to
DRP
(Q501),
SFC
(Q551),
and
DAIO
(OA01)
are
all
normal.
YES
YES
YES
YES
Notes:
o
lf
an
lC
or
its
peripheral
component
is found
to
be
defective,
leave its
pin(s)
unsoldered
or
replace if
with
a
Íunctioning
component.
.
If
a defective
lC
or
peripheral
is left
soldered,
an
"NG"
message
will reappear when
another
lC is
tested.
.
l0s
or
peripherals
found
to be
normal may
be
resoldered.
o
More
than one
lC
or
peripheral
may
be defective
at
a time. Carry out all the troubleshooting
steps even
if
a defective
IC
or
component
is
discovered
before
you
complete all the steps.
The
unit turns off
if no
button
is
operated
for
3
minutes
after entering
Service
mode.
Use a
normal
(new)
tape
for
troubleshooting.
To
exit Service
mode,
press
the STOP
button.
-27
-
PCS
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