Motorola CDM1250 Service Manual

Troubleshooting Flow Chart for 45 W Transmitter Section 8: 3-3
6881091C63-F
2.0 Troubleshooting Flow Chart for 45 W Transmitter (Sheet 1 of 2)
Current
increase
when keyed?
NO
YES
START
No power or low power when keyed
Check Components between
Q3441 and RF Output, Antenna
Switch D3471,D3472
>500mA & <5A
>5A
<500mA
Check PA Stages
Control
Voltage at
TP3402
>1V
>1V
<1V
Check
Voltage at
PCIC U3501
Pin 4
Check Components
between TP3402 and
U3501 Pin 4
Short TP3403
to Ground
NO
YES
Voltage at
TP3402 ris-
es?
Check PA Stages
NO
YES
PCIC U3501
Pin 15 9.3V
DC?
Check 9.3 V Regulator
U0641
NO
YES
PCIC U3501
Pin 16 >4V
DC
Replace PCIC
U3501
NO
YES
TP3404
9.1V DC
If U3201 Pin 3 is high,
replace PCIC
U3501,otherwise
check controller and
FGU
YES
NO
TP3403
>0.5V DC?
Replace PCIC U3501
Check Forward & Reverse
Power Sense Circuitry
(D3451 & D3452)
Check Forward & Reverse
Power Sense Circuitry
(D3451 & D3452)
NO
YES
PCIC U3501
Pin 5 > 1V
DC?
Check Power Setting,
Tuning & Components
between PCIC Pin 5
and ASFIC (U0221) Pin
4 before replacing AS-
FIC

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