Motorola CM Series User Manual

3-4 TROUBLESHOOTING CHARTS
2.0 Controlhead CM160/CM360 Troubleshooting Chart
2.1 Control Head Failure
Back light
OK ?
Check 9.3V on
Q12, U1 and associated
parts and U8
No
Control Head Check
Power-up
Alert Tone
OK ?
Check Speaker
Connection
No
Indicator
LED’
S
OK ?
Check
Q8-Q10, U8 and 9.3V
No
Display
OK?
Check LCD
connections, U3 for 5V,
Osc. pins 1 & 2 activity
SCI thru via U4
No
Up/Down
P1 and P2
Alert Tone
Buttons
OK?
Check keypad resistors
No
EXT
PTT
OK ?
Check Q13, Q802
No
Communication Ok
Check Q803, Q14 and
associated parts
Control Head is OK
YES
YES
YES
YES
YES
YES
No

Motorola CM Series Specifications

General

Brand	Motorola
Model	CM Series
Category	Radio
Language	English