Motorola CDM1250 Service Manual

Troubleshooting Flow Chart for 25 W Transmitter Section 6: 3-3
6881091C63-F
2.0 Troubleshooting Flow Chart for 25 W Transmitter (Sheet 1 of 3)
Current
increase
when
keyed?
NO
YES
START
Check if Pressure Pad closes S5440
Check Components between
Q5441 and RF Output,
Antenna Switch
D5471,D5472,Q5472,
VR3471,Q3471
>500mA & <4A
>4A
<500mA
Check PA Stages
Control
Voltage at
TP5402
>1V
Short TP5403 to
Ground
NO
YES
Voltage at
TP5402
rises?
Check PA Stages
NO
YES
PCIC U5501
Pin 14 9.3V
DC?
Check 9.3 V Regulator
U0641
NO
YES
PCIC U5501
Pin 16 >4V
DC
Replace PCIC U5501
NO
YES
TP5404
9.1V DC
If U5201 Pin 2 is high,
replace PCIC
U5501,otherwise
check controller and
FGU
YES
NO
TP5403
>0.5V DC?
Replace PCIC U5501
Check Forward Power
Sense Circuit (D5451)
Check Forward Power
Sense Circuit (D5451)
NO
YES
PCIC U5501
Pin 5 > 1V
DC?
Check Power Setting,
Tuning & Components
between PCIC Pin 5
and ASFIC (U0221)
Pin 4 before replacing
ASFIC
No power or low power when keyed

Motorola CDM1250 Specifications

General

Display	Alphanumeric
IP Rating	IP54
Frequency Range	VHF: 136-174 MHz, UHF: 403-470 MHz
Signaling	PL, DPL, MDC1200, Quick Call II
Operating Temperature	-22°F to +140°F (-30°C to +60°C)
Power Output	VHF: 1-25W; UHF: 1-25W