Channel Select Error (Apx 2000/ Apx 4000 (Two Knobs)) - Motorola APX 1000 Detailed Service Manual

Troubleshooting Charts: Channel Select Error (APX 2000/ APX 4000 (Two Knobs))
5.8

Channel Select Error (APX 2000/ APX 4000 (Two Knobs))

RTA3
Physical
Posi on (R21007)
Channel 1 1
Channel 2 1
Channel 3 1
Channel 4 1
Channel 5 1
Channel 6 1
Channel 7 1
Channel 8 1
Channel 9 0
Channel 10 0
Channel 11 0
Channel 12 0
Channel 13 0
Channel 14 0
Channel 15 0
Channel 16 0
RTA2 RTA1 RTA0
(R21006) (R21005) (R21004)
0 1 0
0 1 1
1 1 1
1 1 0
1 0 0
1 0 1
0 0 1
0 0 0
0 0 0
0 1 0
0 1 1
1 1 1
1 1 0
1 0 0
1 0 1
0 0 1
Channel Select
Error
Verify opera on of
Channel Select Switch
by using Bu on Test
flowchart
Pass Bu on
Test?
No
Disconnect the GCAI flex
from the front kit flex.
Visually inspect the GCAI
flex for tears or other
damage. For each channel
in error, use the chart to
compare the con nuity to
ground for each pin.
Pass visual
inspec on and
con nuity check?
Yes
Reconnect the GCAI flex to
frontkit flex and power on the
radio. Verify the logic levels at
R21007, R21006, R21005 and
R21004 with chart.
Logic Good?
Yes
Verify board to flex
connec on.
5-25
Yes Verify code plug
programming
No Replace GCAI
flex
No
Replace RF
Board