Troubleshooting Charts; Troubleshooting Flow Chart For Controller - Motorola GP328 Plus Service Manual

Troubleshooting charts

9.0 Troubleshooting charts
INT
AUDIO
NO
J403 Audio
at Pin 2 &
Pin 3
YES
Audio from Pin 41
Check Spk. Flex
Connection
Check U301 NO
LV ZIF
EXT
PTT
Radio could
not PTT
externally
EXT
SPKR
J403 Pin 9 low?
Pin 8 high?
YES
ASFIC U404 Pin
14 & 15 high?
YES
Check
U420 Audio PA
PTT
Press PTT. Red
LED does not
light up
Audio at
YES
AudioPA
(U420)
input
PTT U409 Pin
(U447)
Check
low?
Audio PA
(U420)
YES
NO
ASFIC, U404?
Press PTT
Q502-2 High?
NO
Audio at
Check
Pin 2
Q502-2
U404?
voltage
YES
Check ASFIC
LED should
U404
light up
J403 OPT_SEL_1
NO
& OPT_SEL_2 Check
Pin 8 & 9
Accessories
low?
U409
YES
Pin 52, 6
NO
low?
Check
NO
Accessories
NO
Check
U404
MCU Check
Power Up
Alert Tone
OK?
NO
53
Speaker
Check
OK?
PB504
YES
No
U409 EXTAL=
7.3728 MHz?
LED
YES
Q502,R501
OK?
U201 Pin 19
16.8 MHz
No
Replace
Faulty
Component
5V at U247?
3.3V at U248?
YES
Check
MCU
U409 Reset Pin
94 High?
See FGU
Troubleshooting
chart
MCU is OK

Troubleshooting Flow Chart for Controller

YES Not able to pro-
gram RF Board
ICs
NO
NO
Replace Speaker
YES
YES
NO
Read Radio OK?
YES
NO
NO
See FGU
Troubleshooting
YES
7.5V at
NO
Pin 3/5 U247? 4/
3.3V at Pin 1
U248
YES
YES
NO Check any short to
SWB+,
Vdda or Vddd
YES
5B-29
Before replacing
MCU, check SPI
clock, SPI data, and
RF IC select
Check
Setup
Reprogram the
correct data.
NO
Check
Q400
Replace U247/
U248