Sylvania 6842PF M Service Manual page 34

FLOW CHART NO. 2
Audio is not outputted from speakers normally.
Input audio signal.
Is audio signal inputted to each pins on IC4301
and IC4302?
[****] is the check point on the component side.
When inputting to Video 1 jack...
IC 4302 Pin (13) [C4713 PLUS LEAD] AUDIO1(L)
IC 4301 Pin (13) [J4150]
When inputting to Video 2 jack...
IC 4302 Pin (14) [C4728 PLUS LEAD] AUDIO2(L)
IC 4301 Pin (14) [J4153]
When inputting to component 1 jack...
IC 4302 Pin (1) [CN4711,14pin] AUDIO3(L)
IC 4301 Pin (1) [CN4711,13pin] AUDIO3(R)
When inputting to component 2 jack...
IC 4302 Pin (5) [CN4711,11pin] AUDIO4(L)
IC 4301 Pin (5) [CN4711,10pin] AUDIO4(R)
Is input switching signal inputted to each pins on
IC4301 and IC4302?
[****] is the check point on the component side.
Pin (11)
[CN4711, 3pin]
Video 1
L
Video 2
L
Component 1
H
Component 2
H
Is audio signal outputted to each pins on
IC4301 and IC4302?
[****] is the check point on the component side.
IC4302 Pin (3) [J4181] L-CH
IC4301 Pin (3) [J4172] R-CH
Is audio signal inputted to each pins on IC4801?
IC4801 Pin (8) L-CH
IC4801 Pin (6) R-CH
AUDIO1(R)
AUDIO2(R)
Yes
Pin (10) Pin (9)
[CN4711, 2pin] [CN4711, 1pin]
L L
L H
L L
L H
Yes
Yes
(continued to "A" on next page)
Check lines between Pin (13) on IC4302 and
No
JK4702, between Pin (13) on IC4301 and
JK4702, and service it if defective.
No
Check lines between Pin (14) on IC4302 and
JK4402, between Pin (14) on IC4301 and JK4403
and service it if defective.
No
Replace the Digital CBA.
No
Replace the Digital CBA.
Check lines between each pins on IC4302 and
each pins on CN4711 , between each pins on
IC4301 and each pins on CN4711 and service it if
No
Pin (9) on IC4301,IC4302
Pin (10) on IC4301,IC4302
Pin (11) on IC4301,IC4302
Check +5 V line and service it if defective.
No
Is +5V signal inputted to Pin (16) on IC4301
No
and Pin (16) on IC4302?
Yes
Replace IC4301 or IC4302.
Check lines between each pins on IC4302 and
No
each pins on IC4801, between each pins on
IC4301 and each pins on IC4801 and service it if
Pin (3) on IC4301
Pin (3) on IC4302
1-8-3
Pin (1) on CN4711
Pin (2) on CN4711
Pin (3) on CN4711
Pin (5) on IC4801
Pin (2) on IC4801
L0653TR