Troubleshooting Flow Chart For Controller - Motorola GP Series Detailed Service Manual

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

Troubleshooting Flow Chart for Controller

YES Not able to pro-
gram RF Board
OK?
ICs
NO
NO
Replace
Speaker
Speaker
OK?
YES
YES
Read Radio
OK?
NO
NO
YES
7.5V at
NO
Pin 3/5 U247?
4/3.3V at Pin 1
U248
YES
Check any short
NO
to SWB+,
94 High?
Vdda or Vddd
YES
Chapter 2
Before replacing
MCU, check SPI
clock, SPI data,
and RF IC select
NO
Check
Setup
YES
Reprogram the
correct data.
See FGU
Troubleshooting
NO
Check
Q400
YES
Replace
U247/U248