Troubleshooting Flow Chart For 45 W Transmitter - Motorola CDM Series Detailed Service Manual

Troubleshooting Flow Chart for 45 W Transmitter

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