Motorola CDM Series Detailed Service Manual page 575

Troubleshooting Flow Chart for 45 W Transmitter
2.0 Troubleshooting Flow Chart for 45 W Transmitter (Sheet 1 of 3)
Check components be-
tween Q3441 and RF
output, antenna switch
D3471, D3472, Q3472,
VR3471, Q3471
Check PA stages
Check 9.3 V Regulator
U0641
Replace PCIC
U3501
If U3201 Pin 2 is high,
replace PCIC U3501;
otherwise check con-
troller and FGU
Check power setting,
tuning & components
between PCIC Pin 5
and ASFIC (U0221)
Pin 4 before replacing
ASFIC
Replace PCIC U3501
START
No power or low power when keyed
Check if pressure pad closes S3440
Measure
supply
>4A
>500mA & <4A
current
increase
when keyed
<500mA
Is control
voltage at
YES
TP3402
>1V when
keyed?
NO
Is PCIC
NO
U3501 Pin 14
9.3V DC?
YES
Is PCIC
NO
U3501 Pin 16
>4V DC?
YES
NO
Is TP3404
9.1V DC?
YES
NO
Is PCIC
U3501 Pin 5
> 1V DC?
YES
YES
NO
Is TP3403
>0.5V DC?
Check PA stages
Check power-sensing
circuitry (D3451 & D3452)
Section 11: 3-3
Short TP3403
to Ground
Is voltage at
YES
TP3402
raised?
YES
Check power-sensing
circuitry (D3451 & D3452)
6881091C63-F