Technical Manual

10-23
Chart 21. Zone/Channel select Error
Verify codeplug
programming
with RSS. If
codeplug checks
good replace
U702.
Channel RTA3 RTA2 RTA1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
RTA0
1
0 0
2
0 0
3
0 0
4
0 0
5
0 1
6
0 1
7
0 1
8
0 1
9
1 0
10
1 0
11
1 0
12
1 0
13
1 1
14
1 1
15
1 1
16
1 1
Synopsis
This chart relates to a failure
in reading the zone/channel
select knob. Basic Failure
modes are as follows:
1) Failure in flex circuit.
2) Bad connection.
3) Defective switch.
4) Defective port in SLIC.
Zone/Channel Select
Error.
Verify operation of
zone knob per "Button
Check" flow chart C.18.
Signals
check good
at U702?
No
By studying the
adjacent chart against
the channel numbers
which have errors,
one signal may be
determined to be in
error or verify logic
levels at PH3-PH0 at
U702 for each
channel.
Yes
Verify similar
operation directly at
U1 of controls flex assembly.
U1 checks
good?
Replace
front cover (housing)
assembly.
Repair flex or
connections as needed.
Yes
MAEPF-26035-O
No