(800/900Mhz Dc Switch) - Motorola Handie-Talkie MTX Series Theory/Troubleshooting Manual

No R5/No T5
Voltage
YES
at Q108,
Pin 4?
0V
Voltage
at Q108:
at U202
Pin 5 - RX
Pin 1?
Pin 3 - TX
YES
Check U102
VDC
U202-8
VDC
J301-2
U712-2
Replace P404
NO
NO
VDC
P404-1 J301-1, 20
YES
Replace
Replace Fuse
Jumper Flex
TROUBLESHOOTING FLOW CHART #3B

(800/900MHz DC Switch)

NO
YES
Check Continuity
Between U202-1
& Q108-4
NO
YES
Replace U202
NO
NO
Check
Jumper Flex
YES
VDC
YES
VDC
U712-4
LOW = ON
YES
Replace U712
VDC
YES
VDC
NO NO
Q703-1
HIGH = ON
YES
Replace Q703
NO
VDC VDC
J703-10 J703-8
YES
Replace
Replace CR704
Control Flex
MAEPF-23443-O
YES
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