Troubleshooting Flow Chart For 45W Transmitter (Sheet 1 Of 2); Troubleshooting Flow Chart For 45W Transmitter (Sheet 2 Of 2) - Motorola 6864115B62-C Detailed Service Manual

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Troubleshooting Flow Chart for 45W 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
ASFIC
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
TP3403
>0.5V DC?
START
No or too low Power when keyed
Current
>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
NO Check Forward & Reverse
Power Sense Circuitry
(D3451 & D3452)
TROUBLESHOOTING CHARTS
>500mA & <5A
Short TP3403
to Ground
Voltage at
NO
TP3402
rises?
YES
Check Forward & Reverse
Power Sense Circuitry
(D3451 & D3452)